When the piston rings are installed, there’s a tiny space between the ring ends. That space matters because the rings expand when the engine gets hot—too little gap can cause rubbing or damage, and too much gap can reduce sealing.
Bearings need a very specific tiny clearance to work correctly. If it’s too tight, parts can overheat; if it’s too loose, oil pressure drops and the engine can wear out faster.
Engine break-in is the early running process used to seat piston rings and establish proper wear patterns on new or freshly rebuilt components. The goal is consistent heat cycles and controlled load so rings seal well and bearings/valvetrain components wear in safely.
Head studs are the heavy-duty bolts that hold the top of the engine (the cylinder head) tightly to the block. Using the right lube helps the studs tighten correctly so the engine sealing stays reliable.
A machine shop is where they do the precision machining on engine parts. After they’re done, the engine builder checks everything so the engine can be assembled with the right clearances.
Concept
cleaning fee
Sometimes the shop charges extra to clean the parts after machining. Even then, it’s smart to check that everything is sealed up and clean so oil can flow correctly.
When an engine is built, there are channels that carry oil to lubricate everything. Oil galley plugs are small caps that seal the ends of those channels so oil doesn’t leak out.
This is about keeping the engine really clean while building it. If oil passages aren’t sealed and cleaned properly, the engine can leak oil or get dirty oil that harms bearings and other parts.
Brake cleaner is a strong cleaner people spray to wipe off oil and grime quickly. It can help during engine building, but you still need to make sure the oil passages are truly clean and sealed.
Bore brushes are small brushes made to scrub the inside of the engine’s cylinder walls. Cleaning the cylinders helps prevent leftover grit from causing problems later.
Moroso makes performance parts and also tools for engine building. In this segment, they’re mentioned for a kit that helps clean the inside of the cylinders.
When you machine or modify an engine, tiny metal bits can remain inside. Cleaning the oil passages helps prevent those bits from getting into the oil system and damaging parts.
Main bearings are the supports that let the crankshaft spin smoothly. They need oil to stay lubricated, so the oil passages feeding them have to be correct and clean.
Cam bearings help hold the camshaft in place and keep it lubricated. If oil can’t reach them, the cam can wear quickly because it’s not getting enough lubrication.
An oil bearing works like a “floating” surface that’s kept apart by a thin layer of oil. If the oil can’t flow where it needs to, the bearing can wear out faster.
The main cap is part of the engine block that helps hold the crankshaft bearings. If it’s not aligned right, the crankshaft can run with poor support and the oiling can be less effective.
The cam journal bearing is what the camshaft spins on inside the engine. It needs the right oil flow and clearance so the camshaft doesn’t wear out quickly.
They’re using a hex tool like a simple measuring stick to check that an oil passage isn’t blocked or too tight. If the tool fits, it suggests the oil can flow properly.
Concept
oil passage alignment vs bearing shell openings
People often expect the oil holes in the engine and the bearing to line up exactly. This discussion says that’s not always how it’s designed—what matters is whether the oiling passages meet the build specs and allow flow.
Oil holes are the channels that send oil to the moving parts. The important takeaway is that the hole you see in the engine block isn’t always the same size as the opening in the bearing itself.
Not all bearings are made the same, but many aftermarket brands follow the same oiling and fitment specs that builders trust. If you choose reputable bearings, they’re usually designed to work as intended.
Term
brushes through there
Running brushes through oil passages is a cleaning step to remove debris and ensure oil can flow freely to bearings. It’s a practical part of preparing an engine for assembly, especially when tolerances and oiling paths are critical.
Deburr means smooth out the rough, sharp edges left from grinding or dents. Here, it’s important because rough edges can stop the plug from sealing and can cause oil to leak. Taking the time to deburr helps the new plug fit correctly.
Concept
refresh it
In engine-building context, “refresh it” usually means disassembling, inspecting, and reassembling components (often with new parts) to restore reliability. The key point here is that prep work on oil passage sealing surfaces should be done before final cleaning and reassembly. Skipping steps like removing stake marks can turn a “refresh” into a leak problem.
A thread chaser is a tool that cleans up the screw threads in a hole. If threads are a little messed up, the plug may not seat right and could leak. Using a thread chaser helps make sure the new plug goes in smoothly and seals.
“Filing rings” means adjusting the ends of the piston rings so they fit the cylinder with the right gap. The goal is to prevent binding when the engine heats up and to help the rings seal well.
The cylinder wall is the inside surface of the engine where the piston moves. If it’s dirty or damaged, the rings won’t seal well and the engine can wear out faster.
Term
oil pump passage
The oil pump passage is a pathway oil travels through inside the engine. Porting it means smoothing or enlarging that pathway so oil can move more easily.
Porting is when you reshape the inside passages of the cylinder head. That helps air and fuel move through more easily, which can make the engine breathe better.
The suction side is where the oil pump “pulls” oil from the pan. If it can’t pull oil smoothly, you can get air/vapor in the oil, and lubrication suffers.
Cavitation is when the oil starts to form tiny bubbles because pressure drops too low. Those bubbles can collapse and mess up oil flow, so the engine doesn’t get proper lubrication.
Term
port that
They’re talking about reshaping or improving the passage paths so oil can move better. The idea is to fix the flow first before moving on to other steps.
Threading and tapping means cutting threads into a hole so a matching bolt or fitting can screw in. In engine oiling work, it’s often used to convert a passage closure from a pressed-in plug to a threaded plug for better control and serviceability.
Oil galley passages are the internal channels in the engine block that route oil to bearings and other components. In performance builds, builders may modify these passages to improve flow and reduce restrictions.
Before you start assembling the engine, you do some prep work first. That usually means cleaning and checking the parts so everything fits and works right later.
Cleaning and brushing are about removing dirt and leftover debris from the engine parts. This matters because leftover grime can cause wear and problems once the engine is running.
Total Seal ring is a type of piston ring brand. Piston rings sit between the piston and the cylinder wall to keep combustion pressure from leaking out and to help control oil. Using the right ring and installing it correctly helps the engine seal well.
Term
graphite type product
They’re talking about a special coating that’s used during engine assembly. It’s meant to reduce friction and protect metal surfaces while you’re putting parts together. The color and texture help them judge whether the right material is present.
WD-40 is a spray product people commonly use for loosening things or light lubrication. In an engine build, it’s usually not the final “right” lubricant for bearings and critical surfaces. The host is saying it’s used a little, but the main idea is the other coating.
Main journals are the crankshaft bearing surfaces that ride in the main bearings. Their condition and size directly affect bearing clearance and oil film thickness. Measuring them helps determine whether the crank needs machining (or bearings need selecting) to achieve the target clearance.
Rod journals are where the connecting rods attach to the crankshaft. The bearings there need the right tiny clearance so oil can keep everything lubricated. Measuring them helps prevent premature wear.
Clearances are the small gaps between parts inside the engine. Those gaps matter because they let oil flow and keep metal from rubbing. Getting the clearances right is a big part of building an engine that lasts.
Term
girdle
A girdle is an aftermarket or performance reinforcement piece that ties main bearing caps together to improve rigidity. Because it changes how the block and caps behave under torque, it can affect measured bearing clearances. The speaker notes you may need to install it “as if fully assembled” before measuring.
Oil clearance is the tiny space between the crank and the bearing. “Vertical” just means they’re measuring it in one direction, and the right gap helps oil keep everything from wearing out too fast.
The mains are the bearings that hold the crankshaft in place inside the engine block. The oil gap there matters because it keeps the crankshaft from rubbing directly on the bearings.
The crank journals are the smooth “riding surfaces” on the crankshaft. Bearings sit on them, and the tiny gap between them controls how well oil can lubricate the engine.
A spreadsheet is just a structured way to write down measurements. It helps you keep everything organized and do the calculations correctly instead of relying on memory or mental math.
A dial bore gauge (often called a dial board gauge in casual speech) is a precision measuring tool used to check internal dimensions and clearances. Here it’s being zeroed on a known reference journal and then used to compare other journals for consistent oil clearance.
This is a “double-check” measurement in a different direction. It helps confirm the bearing cap is installed correctly, because a wrong or offset cap can make the gap uneven even if one measurement looks fine.
RPM means how fast the engine spins. When RPM is higher, the engine parts move faster and heat up more. That can make it harder for oil to keep everything separated, so builders plan for it.
The oil film is the thin layer of oil that separates metal surfaces inside an engine bearings. Under high RPM and load, the oil film can thin out; if it fails, the bearing can contact the shaft. This is why clearance and oil viscosity are so important in performance builds.
Idle oil pressure is how much pressure the oil pump makes when the engine is just idling. If the engine has bigger clearances, oil can escape more, so pressure drops. Lower idle pressure can be a problem for daily driving.
20W-50 is a thicker engine oil grade. Builders use it to keep oil protection strong when the engine is running hard or has bigger clearances. It can be less friendly when the engine is cold, which is why it’s not ideal for everyday driving.
Straight 50 is an oil that doesn’t change viscosity much with temperature—it stays thick. That thickness can help protect bearings when the engine is hot and running hard. But it can flow poorly when cold, which is why it’s not great for commuting.
Viscosity is a measure of how thick an oil is and how it flows at different temperatures. Higher-viscosity (thicker) oils can help maintain oil film strength when clearances are larger and oil pressure at idle is lower. The tradeoff is that thicker oil can flow worse when cold, which hurts drivability and lubrication during warm-up.
Concept
race engine vs street truck
A race engine is tuned and built for hard use in a controlled way. A street truck has different everyday conditions, so using race-only choices can cause reliability problems.
Don’t build a truck for “maximum performance” if it’s meant to tow or drive daily. Parts that work great for racing can wear out faster or behave differently under normal loads.
Main clearance is the tiny gap where the crankshaft rides on the main bearings. Getting it right helps the engine stay lubricated and prevents overheating or premature wear.
Concept
mega power builds
Some builders chasing huge horsepower change the internal clearances more than you’d see on a normal build. That can help in extreme conditions, but it can also make the engine less forgiving if it’s not set up right.
Rod bearings are the bearings that connect the pistons’ motion to the crankshaft. They need the right fit and oil supply so the engine doesn’t wear out quickly.
Term
HX
HX is a thicker/looser bearing option that gives you a bit more clearance than the standard H bearing. Builders use it like a dial—choosing HX (or part of it) to get the exact spacing they want inside the engine.
H bearings are special engine bearings that are meant to fit a tighter, more controlled clearance than stock. When you build an engine, that clearance matters because it affects how smoothly the crank moves and how well the engine stays lubricated.
“Dial in clearance” describes the process of using measurements and bearing selection to achieve a precise, repeatable clearance target. The episode frames it as predictable and spot-on when you record journal thicknesses and then mix bearing halves (H/HX) to match the desired spacing.
Term
main galley
This is about the main bearing area—where the crankshaft sits in the engine. Builders measure the crank’s journal surfaces so they can choose the right bearings and get the correct fit.
The main journal is the part of the crankshaft that rides on the main bearings. Measuring its thickness helps you pick bearings that create the right tiny gap for proper lubrication.
Concept
800 horsepower build
They’re talking about how engine-building choices can change depending on how much power you’re trying to make. For a big-number build, you may want slightly different clearances so the engine can handle heat and stress.
Concept
non water cooled block (solid block)
Most engines use coolant to keep temperatures under control. If a block is described as “solid” or “non water cooled,” it means the usual cooling approach isn’t there, so heat builds differently. That can change how much parts expand, which is why clearances might need different setup in extreme cases.
Sled pulling is when a truck tries to pull a heavy sled as hard as it can. The engine is under heavy load for a long time, which can stress it more than normal driving. So engine builders often set up clearances and parts differently for that kind of use.
Cummins makes diesel engines that show up in a lot of trucks. When the speaker says “Cummins range,” they mean different Cummins engine types/builds. They’re talking about how much you need to change clearances and parts depending on how hard you’ll use the engine.
The bolts that hold the rod cap on have to be tightened to the right spec. If they’re too loose, the bearing can move and wear out; if they’re too tight, the parts can distort or run hot. That’s why builders torque them carefully and usually use new hardware.
A rod vice is like a specialized clamp for holding a connecting rod while you work on it. Soft jaws are the cushioned/grippy inserts that hold the rod without scratching or bending it. That helps keep the rod straight and prevents problems later when the engine is assembled.
Connecting rods are the parts that connect the pistons to the crankshaft. When you build an engine, how you torque and assemble the rods affects how the bearings sit and how smoothly the crankshaft spins.
A torque wrench tightens bolts to an exact tightness instead of “by feel.” That matters on engines because the bolts need to be tight enough to hold parts safely, but not so tight that they cause problems.
Rod clearance is the tiny space between the bearing and the crankshaft. The engine needs the right amount of space so oil can get in and keep everything from rubbing directly.
Term
dimple die
A dimple die is a tool that makes a small mark on a metal part. Builders use it to keep track of which cap goes with which rod so everything goes back together correctly.
Company
Carillo rod
Carrillo makes aftermarket connecting rods. The point being made is that some rods are designed so they only fit together one correct way, and mixing them up can cause poor alignment.
Numbering rods is a way to remember which parts go together. Because each rod and cap can be a little different, labeling helps you put them back exactly the same way.
The connecting rod is the part that links the piston to the crankshaft. The rod cap is made to match that specific rod, so you should keep them together—otherwise the fit inside the engine can be slightly wrong.
Think of the rod cap and rod like a matched pair. Even if you can physically swap them, the fit inside the engine may not be right, which can hurt reliability.
Some engine parts are assembled with exact torque settings and then finished to the right dimensions. That’s how they get the correct “fit” and clearance—so swapping parts can make the fit too tight or too loose.
Some factory parts are marked so you can tell which pieces belong together. If the rod and cap are a matched set, the serial numbers help you keep them paired correctly.
Pin clearance is the tiny space between the piston’s pin and the rod’s bushing. It needs to be just right: too tight and it can stick when the engine gets hot, too loose and it can rattle or wear faster. That’s why people measure it before final assembly.
A connecting-rod bushing is the bearing surface inside the rod that the wrist pin rides in (common in many rebuilds). When rods are reconditioned, the bushing may be replaced or resized, which directly affects pin clearance. Correct bushing fit and measurement are essential for durability and quiet operation.
Concept
clearance trade-off (heat expansion vs noise/wear)
The segment describes a clearance trade-off: tighter clearances reduce slop and noise, but they risk interference when parts expand with heat. Looser clearances avoid binding but can increase cold slop and contribute to knock-like noises and wear. Engine builders tune clearances based on the intended use (street vs race) and operating temperatures.
Rod knock noise is a knocking sound from the engine bottom end. It can happen when parts have too much looseness, especially when the engine is cold. If you hear it, it often means the clearances aren’t right.
This is the tiny space between the piston and the cylinder wall. If the gap is too tight, the piston can rub and overheat; if it’s too loose, you can get extra wear and poor performance. Machinists measure it so the engine fits correctly once it’s hot.
It means you shouldn’t just assume everything is correct—you should double-check the important measurements. In engine building, a small mistake can lead to big damage, so verifying helps you catch problems early.
The piston skirt is the part of the piston that slides along the cylinder wall. Since it’s the part that actually fits inside the cylinder, measuring it helps you confirm the engine has the right clearance. That’s important to prevent rubbing and excessive wear.
An “oblong” piston isn’t perfectly round like a circle. It’s shaped so the fit and clearance are right in different directions. That’s why you can’t just measure one spot and assume everything is fine.
Pistons aren’t perfectly the same thickness from top to bottom—they’re shaped with a taper. That means the gap to the cylinder changes depending on where you measure. Measuring the right spot gives the most accurate clearance.
A “Molly piston” usually means the piston skirt has a special coating to help it slide smoothly and resist wear. When you measure it, you want to avoid scratching that coating. That’s why some pistons have a marked area for measurement.
LIVE
Hello, everybody. Welcome back to the power driven podcast today.
We're talking about engines. We love engines. We love making engines,
building some new awesome engines for Myers UCC build.
We thought it might be a fun time to talk about some tips and tricks we use
to build engines, break it engines, all kinds of stuff.
And so we're talking about engines today. Will, what you got?
I mean, we, this is a popular topic that comes up.
People are asking us about ring gap, bearing clearance,
piss in a wall clearance. How do you break it in? What oil do you use?
For sure. Break it.
What Loctite do you use? What lube do you use on the head studs?
And so we could go very deep on this topic.
So let's, let's just start right away.
When you very first get a block and we will assume that you paid a machine shop
or somebody to machine it. What's the first step you do, Myra,
when you first get a block? Well, first, I mean, I would say inspect,
make sure the machine shop did everything they were supposed to do.
But second clean, like this is a common one that I've seen and I don't understand.
It's like the, in order for the machine shop to do their job,
they pull the oil galley plugs out of it. They may or may not supply you with new
ones. They may or may not install it.
It is not on your machine shop to make sure you plugged all your oil galleys
and they don't have like, obviously, if you pay the cleaning fee,
you should at least be inspecting it as the builder. You should be inspecting it.
And so I've seen people like put their trucks together and they got a big old
leak because they didn't put an oil galley plug in and they're trying to blame
the machine shop. Like, yeah, you're the builder guy.
Yeah. If you should know, if you're building an engine,
hopefully you have some kind of base knowledge about what needs to happen,
but how do you get that knowledge if you've never built one? Okay.
That's understandable. But there are oil galley plugs that plug the ends of the
oil rail, galley, whatever you want to call it that supplies oil to all of your
engine. It's like the, the, the tubing, the plumbing, the plumbing of your engine.
And they had to drill those plumbing from the outside to make those holes.
And then you plug the outside and now it works. So make sure those holes are
plugged in. And so how do you clean out those oil rifles though?
Cause I know the first time I was building an engine, I sprayed a little
brake clean in there and air blast is like, that's all I could do,
but I know that's not proper.
And we're now on our third term, oil galley, oil rail, oil rifle.
So we have three terms describing the same thing.
Fourth term already for the same exact thing.
So I mean, yeah, I mean, break clean gets you a long ways.
I like to like, we, we have a parts washer that does a really good job.
And so I generally just throw it through that and then break clean it to victory.
But back in the day, I just use a quick garden hose and soapy water.
And I would just let there and rinse everything out.
Use some bore brushes.
And Morosa has a nice engine kit, like very inexpensive on some of it,
like Morosa engine brush kit to clean out your cylinder bores, your engine rifle.
And some of those are long. They're like, some of those are almost three feet
long designed for sizes.
And so on a Cummins block, we'll talk.
There's like a main oil galley or rifle.
One goes the little passage.
So one comes from the passenger side of the block and intersects.
And that's where the oil cooler feeds in that intersects in a T to a long,
a long oil galley or long oil passage on the driver's side of the block.
And that's where you need the long, you know, 30 inch brush or so.
Or, you know, if you go from each end, you need about 15 inches of brush.
I like, yeah, the kit comes with a nice long one.
That way you go all the way through.
So, yeah, take your time here and getting all you don't want to have
old machining particles, metal bits, metal flakes.
I mean, you're going to, as you start your engine,
you're going to have metal flakes come out naturally,
but you don't want the leftover stuff there.
So take a little bit of time here and make sure things clean.
And as you're doing that, there's also oil passages from that
to feed the main bearings and then from the main bearings,
there's little whole passages in the main bearing saddle
that also feeds the cam bearings.
It's a great time to make sure your machine shop put the cam bearing in right.
If you can't put the brush through there, there's no oil going to get into the cam.
I've seen that happen to people.
I think common spec.
So people, I've seen it where people think like, oh my gosh, the oil bearing
or the, like for the main cap or the cam journal bearing,
bushing, whatever is offset a little bit.
It's pinching off the flow.
I think the common spec for that is legitimately just to put a four millimeter
hex driver through it and if it fits, you're good.
And so I'd do only do a five because I'm overambitious, but.
But it is interesting, even when you put like the main bearings in,
you'll notice the holes don't line up and the bearings in the engine.
Why is that? So they're using their size in the hole by putting the whole offset
and the bearing hole in a different location.
So you have like a half circle showing or a little, you know, whatever it is,
but they're not. It's not lined up.
Just realize that we've had people ask, why doesn't this lineup?
So this is, you maybe see like one of the first pro tips,
the oil bearings, just because there's a hole in the block that's an eighth inch,
doesn't mean the hole through the bearing is supposed to be an eighth inch.
They've designed those to, you know, and basically the aftermarket bearing
manufacturers have copied the common specifications.
Maybe they've made changes as pro builders over the years have suggested things.
But for the most part, like if you buy the right stuff, it's, it's going to work.
Five millimeter hex driver can go through it. You're good.
You're hyping in an all oil holes going in your mains. Yep. Yep.
And so yeah, I'll run some brushes through there. Get it good and clean.
Then you should, you should hopefully have the ability to measure some stuff.
You need to, unless you're a little taro, you should measure.
For the biscuit, you should probably measure stuff.
So I'm going to put a builder would have, well, go ahead.
So I was just going to just circle back to what we were talking about,
your oil galley plugs, um, two things.
First of all, if your old engine was a performance build and someone staked
the oil galley plugs in, make sure that you remove any, like you take a grinder,
whatever, and deburr the stakes that they were, they had that way.
It doesn't put a score through your oil galley plug cause a leak.
When you reinstall a new one, you were saying, yep, like a week before UCC
because some guys will stake oil galley plugs.
They think that they're helping them that way.
And when you go to refresh it, if those stake marks are there, when you go to
pound a new oil galley plug in there, like you said, it'll, it'll cause a leak.
We've been there and done that.
And hopefully you clean up the burst before you clean the block.
Otherwise you're then now, and something half butt cleaning it again to fix your
grinding. I would a hundred percent recommend is get yourself a thread chaser kit.
You can go on Amazon again.
I'm so cheap for just a cheap one.
And just chase every single hole in the block.
Then a, if you have a stripped hole, then you can fix it before you've cleaned
everything, but also if a dirt dober has put a mud nest inside one of those holes,
you're not trying to remove that on your clean engine.
Now we're talking where some people said, some people know what a dirt dober is.
It's like a mud dober wasp.
It's like a wasp, but instead of stinging you, it just collects mud.
It's an interesting thing, I guess, but Midwest people will know plenty of those.
So first you're going to inspect, you're going to clean.
Yep.
Then we're going to say you're going to measure, right?
Yeah.
What about, I mean, you like to file rings before you actually clean the block.
I do.
I kind of think that's really before I clean, final clean.
There's a few things I like to do first, like you said, go through, check all your
threads, make sure that stuff's done.
I mean, you're putting rings in and out a whole bunch of times when you're
threading them and getting your, set your clearances.
So I'll kind of like wipe down like some break clean, the upper bore of the
cylinder wall, and then I'll do my, my rings that way I have that done.
And then I can file final clean it.
And I'm not bringing in stuff all the time back into the engine block.
So I like to do all my like modifications to whatever's going in there
before I do final cleaning.
So once again, pro tip on this modification.
So there's an inspection begin with, then I would say any modifications,
thread chasing you're doing.
I like to port the oil pump passage.
I like to cut those edges back so that I'm, you know, I like porting cylinder
heads.
So I want my oil system to have the best chance of flow.
And the most important, in my opinion, is on the suction side to get the flow.
Cause that's where it'll cavitate and separate on the pressure side.
It's going to make another PSI and, and hopefully push through that on the
suction side.
It can't make more PSI.
It only has atmospheric pressure on the suction side to work.
So I like to port that.
So obviously you do that first.
Yep.
Todd likes to file his rings first.
So he lightly cleans the bore and, and sets your ring gap in there.
And so you're kind of putting dirtier rings in and out several times.
Some guys like to thread and tap their oil galley passages.
They don't like the little pressed in oil galley plugs.
And so if you're going to do that, you would thread that first.
If you're going to run an oil accumulator, some guys run those
acu-sum things on like a race truck that has hard deceleration.
Well, on a six, seven comrade block, there's an oil galley plug that would
be kind of right behind where a pee pump would go on the passenger, on
the driver's side of the block.
It's a good time to knock that out and thread that right there.
If you need a good half inch MPT or three eighths MPT, three eighths MPT,
half inch MPT to feed and acu-sum.
So some of that's consideration, but most people that are doing that
kind of stuff probably don't need these tips anyway.
So if you're doing that, you're probably not listening to this, but it's true.
But at the same time, it's very easy to get your block.
You got straight from the machine shop.
Okay.
You get so excited about building it.
You're like, okay, no, stop, pause.
Think through this logically.
What do I need to do to this block to make it so it's ready to build?
And I can just like get it.
And cause like, I mean, one thing that's really nice is you get it all inspected.
You get a clean and everything you get it done and you roll it into the engine
room and you don't have to, you don't have to like cart it around back and
forth a bunch of times.
You get it in there, you're done.
You don't like, oh crap, I forgot this.
Go take it back and then clean it again.
So yeah.
Yeah, it's good.
So once you're, once you've kind of done your pre modifications, you know,
we're talking about cleaning, brushing and stuff.
I do cylinder wall preparation quite a bit.
I spent a lot of time making sure that some wall is super clean.
And I put on that total seal ring.
That green, the green, it's kind of a graphite type product.
Yeah.
It's a dry product because you kind of insult a little bit WD-40.
And if it's green, it's good.
If it's brown, you still have old material from machining on your cylinder
walls and you need to wash it down some more.
So I spent a lot of time in my cylinder walls.
Um, and then I'm kind of on to assembly really, I guess, I'm measuring stuff.
I'm measuring the, the, uh, rod, the journal, the rod journals, the main journals,
the bearings, all that stuff.
And so when we're measuring, this would be a great time to talk about
clearances a little bit.
So let's just start at the bottom end because that's the bottom of the engine.
So you're going to check your main bearing clearance.
So to do that, you would install your main bearing in one of the mains.
Well, all of them techniques, you should measure all of them.
And you're going to actually torque them down.
So if it has a, if it has a girdle or something fancy, you need to put it
like as if it's fully assembled, it's going to take time.
If it's a stock milder engine, you're just going to torque the mains in there.
It's whether they're 12, 14, if they're main studs, you know, with a proper
air, you wouldn't hear about the crank was in it.
And then you're going to put that bearing in there.
You're going to torque it in there.
And then you're going to get a, a mortgage in there, measure the clearance there.
Then you're going to take that on a set of mics, and then you're going to
mic the crank journals on the mains and see what your vertical oil clearance is.
And so two parts of that, I, I'm a big believer in just writing down your numbers.
And if you do it right, you have a spreadsheet and that way it also does
a lot of the math for you.
And so what I will do is I'll measure the crank journals, all seven, and then
I'll zero it on number one, and then I'll zero my, um, dial
board gauge on that same number one.
And so then in the spreadsheet, you just tell it like, okay, like maybe
that journal is a half a half a thou bigger than the rest of them.
Well, you can just say like in the spreadsheet, like, okay, this is what I
zeroed my dial board gauge at, and you just write down all your numbers for
all the, all the journals, all the way down.
And now you've just got accurate clearance for every single one.
And then something I do as well is when you got that dial
board gauge in there, also do a diagonal check.
You don't really, I don't record it, but you just want to make sure
like the cap, like if the cap was backwards or you got the caps mixed up
or something like that, if you, that vertical might be right, but if that
caps offset, you might only have a thou clearance or 10,000 clearance on a
diagonal with the vertical being correct.
So it's just a double check.
Make sure you got the right parts in there and everything's machined
around and everything like that.
So yeah, your tightest spot should be the vertical.
That's how it should be.
You should have about half thou, thou bigger, diagonally, just because of
how the bearings are designed.
And then let's talk oil clearance.
So a factory coming back is two to five thousand ridiculous to me,
but yeah, it's a huge range in performance engines.
Generally the higher performance, the bigger they make the clearance.
Two things stuff moves a lot as you make more power.
And so you need more room for stuff to move and there's more RPM.
And with more power, stuff's going to heat up faster bearings.
It is going to push through the oil film and touch the bearing once
and while it's going to put more heat there.
So you want generally more clearance, the more RPM, the downside of that
for a guy building a tow truck or street engine, big clearance means
when your oil is hot and that idle where your oil pump spinning slow,
your idle oil pressure will be lower with big bearing clearance.
Which is why when most people do race engines, the big clearance
is running a much heavier oil, thicker oil, like a 20, 50 or a straight 50.
I mean, they're running a much, much thicker viscosity to high
viscosity to make up for that very problem.
It doesn't run as well.
So it's not ideal for like a daily driver because your cold oil flow
is going to be worse.
So that's why you wouldn't like say I want to have a street truck.
It's one of the reasons you don't put a race engine, your street truck,
you don't put a race transmission behind your tow truck.
Like as always build for what you're doing.
Yeah.
So then the clearances wise, the loosest I've ever seen on an engine
that was running fine was like six thousandths main clearance.
Some of those big mega power builds I see from like Midwest builders,
they like to really loosen up that clearance.
The tightest I think I've seen, I mean, I think I've had some stuff
down at two thousandths and it was fine, but it made me nervous.
You know, what would you say?
I haven't torn apart a lot of like performance builds that weren't
together enough that I could measure.
But I mean, just from what we've built, I mean, I like shooting
for the, if it's like a stockish build, I want it to be like three,
something three, three to four main, main bearings, main bearings.
Yep.
Three to four rod bearings.
Correct.
Yep.
Three to four on the mains, like kind of like towards the like three
to quarter to three and a half.
And what's nice about it.
And this is like something that you told me originally that I thought was
like super janky, but it turns out it's actually a common practice is
that if you're building an engine that uses H bearings, you have H and HX.
You can mix and match.
You can put an H on the bottom, HX on the top.
And that way you can really nail your clearance the whole way across the block.
Now, for the guys that don't know, H is an upgraded kind of performance bearing.
And then HX means it has an extra thousandth of clearance.
Yep.
If you use both the upper and lower half, if you only use half of an HX,
you generally are going to increase half a thousandth of clearance.
So you can kind of use that to dial in there.
They are super predictable.
Yeah.
Yeah.
And so, so yeah, you can just like, because you measured all of you
measured and recorded all your main galley or main journal thicknesses.
Now you can go in and, you know, hybridize some HHX, whatever, to get all your
clearance is like basically spot on where you want them.
And yeah, it's really nice for that.
And like, like say, I liked between like three, three, three and three
quarter for like a lower call, like 800 horsepower build.
And then you start talking higher, like opening up a little bit, just so
things have something, so a little bit of place to move.
So four plus four ish.
Yeah.
Kind of hover around that for a quarter.
And I think that's kind of where we've never, yeah, we've never really
needed to go beyond from what we've done.
We've never needed to go up to that six thousandths.
We don't, we're not subplonging.
We're not living at the higher p.m.
for the amount of time that they are.
And maybe on a, on a non water cooled block, like a solid block, you know,
and things are moving around, you know, and you have to put it, you know,
maybe that's where that would make sense.
But yeah, for the stuff we've done, we've not had to go in that radical.
We haven't made top level sled pull trucks either.
Both in the Cummins range, which is quite wide.
You got almost everybody covered in that range.
Yeah.
Um, rod bearing, same thing.
So the rods, the, the clearance specs a little tighter on that two to four is
the factory spec, a little bit smaller of diameter.
So that makes sense.
They'd be tighter, but, um, yeah.
And again, I don't think we've ever really had to go beyond out of the
specs either.
Now, when you check rods, the way you would do that is you would
then put the bearing halves in the rod, you would torque the rod bolts down.
So a lot of people have a nice, like a rod vice that's got soft jaws to clamp
the rod because you get some of these aftermarket, you know, performance
rods, it torques 120, 530 foot pounds.
That's hard to hold a rod to 130 foot pounds with a big old tank of a torque
wrench.
So, um, yes, you need a, you need a vicer way to hold the rod, torque it with
the bearing in there, measure the clearance.
Same thing that Meyer said, Mike, all the journals and sometimes you
play musical rod bearings to get your rod clearance.
That's what's nice about rods is that you can start playing musical parts
and like you got a big draw journal, put the big, um, rod on that journal.
And you can also really get a very consistent clearance the whole way across.
Doesn't matter that much now, but it makes me feel warm and fuzzy.
Now a pro tip on rods before I disassemble them, I like to mark on the end either
with a dimple die or paint because you can flip the caps around on some rods,
factory ones, you can't, but it's, I've had some waggler billet rods before
that caps got flipped around and nobody knew.
And they were close enough to line up.
They don't really fit together.
You have to be kind of dumb to assemble a waggler rod backwards, but like a
Carillo rod, yeah, absolutely.
It's just a little dowel thing.
Oh, maybe that was Carillo's.
I was thinking about that.
So I like to mark hard to do that.
So I like possible, but hard, but I like to, yeah, but I like to mark the rod
ends before I go, something I do is I actually number them one through six.
And so the one that I get for number one is when I'm planning to be number
one forever, then when I'm going to build the engine, I don't have to remember
which piston.
So I actually write one on both the rod and the cap on the same side with
a permanent mark so that, so that I know.
And, and anytime I pull that engine out or whatever, another thing you need
to know about piston rods, you can't put the cap on one rod onto another rod.
You need to keep the cap with the rod.
It was done because that was put together, torqued and honed to size.
So you'll notice like on your factory Cummins rods, they have serial numbers
on the side and that's really the cap and the rod match.
So some of the aftermarket doesn't.
So you need to make sure like you number it number one, one, you don't put
the wrong cap with the wrong rod because it'll go on there, but it's not going to be round.
So make sure that you keep the cap with the rod that it came with forever.
Yeah.
That's what I like.
You're talking about marking them.
I like to do the same thing.
And I, I want number one rod to be number one rod and number six, number six.
However, if I measure things and I know that number one will fit better in
number five way of the road, like if you care a lot, you can put it in your
spreadsheet, say like number five rod is going in number one.
That's what I'll do.
Um, and then I'll, I'll like a little, I'll either scratch with like a pocket
knife or like dimple them that way they can go through the parts washer or they
can get blown up and run and I can take it back out and see.
And no, like, yep, that was number five.
Like I must have gotten it from cylinder one or whatever, wherever the spreadsheet says.
Now, to be technically correct, you should also measure the pin clearance,
which is especially important if you're doing factory rods and someone
reconditioned them.
Um, and then I guess a used engine, if you were trying to not redo the bushings,
you would want to, you'd want to check that.
But same thing, you're going to put a, you're going to put a dial
mortgage in the, the pin bushing and, and that now pin clearance is it's a wider
topic.
Um, I would say you can go as tight.
I don't even know the coming spec off 10, but I would say it's about seven, seven
and a half tents, like just under a thou, but I think I would not recommend
somebody go less than a thousandth.
And then we've had some race rods.
I've had over 2000s of clearance because the pin was flexing and we needed more
room in there so that it wouldn't snag the bushing.
But the problem is you get 2000s when it's cold, you might actually get a little
bit of a slop or almost like a rod knock noise.
So generally you want to stay in that, I'd say thousandth to down half
range is pretty normal pin clearance, but, um, I've had instances where we've gone
bigger successfully on race engines, not million miles, you know, street motors.
So, um, just kind of talk about that.
We talked about clearance, um, part of your, your checking and clearance, you're
going to want to check your piston to wall clearance.
Hopefully you told the machine shop what you wanted there, but we should hit
on that a little bit, trust, but verify.
Yeah, we like to, when we machine blocks, we like to have the piston we're
going to use with that, if possible.
So some, in general, the manufacturer's piston, you know, consistency is close
enough, you don't have to do that, but if you can, it sure is nice.
And you really get just the right way of measuring a block.
Like if we're machining the block, this is the way you do it is you, you measure
the skirt of the piston.
So you want to measure like diagonally to the pin about an inch from the bottom
of the piston.
That is the biggest diamond.
You mean perpendicular to the design, not diagonal perpendicular to the pin.
Yes.
And about an inch up from the bottom of the skirt.
That's the biggest time.
If you look at a piston, it is, it's a big taper.
It's oblong and it's tapered all the way up.
So if you want the actual clearance, that's what you kind of need to measure.
And if you look at like a coated skirt, like a Molly piston, they have a little
window right there, right where they want you to measure.
Like that is what that's for.
So you can measure without scratching the coating off.
Um, but either way, it doesn't matter if just get your measurement there.
That's where you'll get your diameter from.
And then you zero a set of dial or gauge on it and then you go in your bore
and then you can measure it in a couple of spots and get your clearance.
Couple of spots side to side and up and down.
Yep.
All the way up, all the way down.
And there's factory specs.
And I wish I could cite them off the bat.
I want to say like it's kind of, there's a factory spec for how oblong and how
much taper you can have.
And I want to say it's like something ridiculous, like two thousands of taper.
And might be three.
It's a lot.
Wow.
That seems like a lot of work from the end, but on a new thing with modern
equipment, there shouldn't be any taper in there.
Yeah, I mean, a new, a new, uh, any modern machine shop should have zero
problem getting, I mean, so tight, you can't measure it with a normal thousand
dial bore gauge.
That's the thing really satisfying about like when we use our home machine is
I'm used to seeing a little bit of taper with like the old machines and stuff.
We've had people like our machine shop use in the past, we got this one and I
go in there and measure and it's just like money just everywhere.
Like, and you can like, and go from cylinder to cylinder and they're all the
same, like it's freaking sweet, but yeah, like, I want to say it's like two
thousands of taper and was it like a thou or something of oblong or something
like that quick serve comes quick serve has all those specs.
I don't remember them off the bat, but just some general thumb, a stock, I
think the minimum is around four thousandths, piston to wall clearance might
even be on some of the newcomers might be like three and eight tenths or
something just under four.
If you are a totally stock power level, Cummins has figured out that that
that that's great.
And honestly, the tighter the better, as far as longevity, there's less ring
rock and whatnot, but at the same time, if you have any kind of a tone or a
chip or anything, don't go on that bottom minimum spec.
You're going to rub stuff your your risking damage for maybe a half a
percent improvement in longevity or blow by or something like yeah, there's age
long saying that like you make it too loose and you'll know, but you make it
too tight and everyone will know it's too loose.
Maybe it'll be a little bit louder or a little bit more haze or not haze, but
like blow by whatever you make it too tight.
When you're on the side of the road, no one's passing you.
They'll know.
Cause you're not seized, but like our blocks that we sell, we advertise that
they're about two thousandths bigger.
So, you know, your max spec on stock is, you know, right around six thousandths
pissed in a wall and like a six, seven.
Um, and it's some exact number, like five and nine tenths or something
like that, but basically six thousandths.
And so, you know, we'll make our, our, like our 800 horse block.
I think we, we advertise there's two thousandths more pissed in a wall.
So if they're around eight max, you know, you're in that six to eight range.
And then our, our higher, like our stage three block, we're talking serious power.
Yeah.
That's going to be up there.
Almost 10,000ths pissed in a wall, you know, eight to 10, you know, range.
Um, I definitely over the years, I'm a bigger fan of enough pissed in a wall.
Every engine I've ever pulled apart that like serious scuffing was a result
of two tight pissed in a wall.
Now that we've gone like bigger, like we plunged as a part of like, gosh,
just seems brandy or Sunderwald doesn't get scuffed by your piston.
It's a better ring sale.
So if you, if you need the clearance, I'd rather be on, I'd rather air on the
big side than the small, because if you're a little bit small, it may not ruin
your engine, but you'll scuff your cylinder walls.
You have worse ring sale.
You have more blow by you'll still drive and you can feel good that you have tight
clearance and know that you have crappy combustion pressure containment.
Yeah.
Now, um, one pro tip on pissed in a wall that's kind of commonly known on forums
and stuff on a 12 valve, we like to run more clearance on number six.
It seems like that one scuffs first from heat.
And so we like to give it an extra thousandth, half a thousandth to a thousandth
of clearance.
So if you're building the engine so that all six will rub at the same time,
basically you would want, you'd want number six, a little bit bigger.
We used to make number one, a little bit bigger too, because that seems to run a
little hotter and five gets slightly more heat.
So because I'm the one that hit and, you know, start stop on the machine.
Like I just kind of do what I want.
What I do is let's say I have eight thousandths pissed in a wall.
I'll do that on two through four.
And then I'll add another two tenths for one in five and then add another four
or five, whatever, tense for six.
So six, so two through four will be eight.
One in through one and five will be eight point two.
And then six will be like eight point four, eight point five.
So that's kind of how I split that.
So we kind of like pro level stuff there, but like you can, you can dial that in
when you have your own machines and equipment.
Some guy was like, Oh, you, he's like, you don't have a cool and bypass on your,
on your tow truck.
He's like, you're going to scuff number six.
And I was like, I don't know.
I was like, I'll put money on it.
Six will not be the first to scuff.
But we get people all the time asked, pissed in a wall clearance.
And that's why it's a tough conversation to say.
Cause if you buy a block from us, we don't make all six exactly the same size.
We make number six cylinder a little bit bigger because we've learned that.
So if a customer needs eight thousandths pissed in a wall, well, if they need
eight on two, three and four, they need more than eight on number six.
And so we, we bumped that up.
That's where we kind of give you a range of what our blocks are.
Our guy machine in the blocks knows exactly what they're supposed to be.
It's easier to just say the range is eight to 10 or whatever.
Cause because of that, but, but to help you guys out, you need a little bit
more clearance on number six.
Now the sticky point when you measure pissed in a wall clearance, if your block
was torque plate owned and it's a 12 valve, once the torque plate comes off,
it's not going to measure round.
You're going to be like, this machine shop screwed me.
My bores are egg shaped.
And in that case, that's where you're kind of getting into the like gray area of
like, can you really check the machine shop?
Or are you just going to kind of hope they did it right?
I will say I've never seen it distort more than two thousandths.
So if it's more than two off machine shop screwed off, one thing you can do is
you measure, so at the top of the bores where the deck, the, the torque plate
is the most where it's going to be pulling.
Generally when it pulls, it pulls the stud out.
So when you take the torque plate off, the stud will be closer in.
So if you measure in line with the, where the studs are, it'll be a smaller
diameter than if you went like, you know, parallel with the block.
But if you measure the bottom of the bore, that's very, very, very little distorted.
There's solid solid metal.
That should be pretty round.
So that's where you can get your numbers.
And you kind of just like hoping that like, yeah, you're measuring some weird
stuff on top.
Hopefully it's good with the torque plate.
I'd say six or seven blocks move less than a half a thou, maybe, maybe a quarter
of a thousandth.
So they're, you know, within what most people can measure that aren't experienced
machinists, you're probably going to think it's round.
And this is where, like, as far as a measuring trick, um, if someone else
machined my block and to where I just want to make sure that they're in the
ballpark and they kind of spitballed correct piston to wall, the right way,
like we said, measure the piston, use the dial bore gauge, get your exact measurements.
You can measure it in multiple points in the bore.
If I'm confident my machine shop, whoever it was, did it correctly, but I just
want to kind of verify, I'll use the other gauges and the piston.
So you just grab like, I should say you think you have seven thousands
pissed in a wall, grab a three and a four, put it, put that and the piston
skirt down in the bore, just slide it down.
And if it fits kind of snug, you can go to eight and go to six.
You can kind of see that's actually a really good way.
And it's really dummy proof.
Like, yep, I'm in the ballpark.
We should be good to go.
Cause those small filler gauges are flexible.
That's why you use a 10 or what our seven, like it's pretty stiff and it
doesn't want to flex around the piston because you're firing it to contour
to the piston and it's just a good, like a dummy proof.
Like you can do that in 10 seconds or less and 20 seconds, whatever.
And just make sure you're in the ballpark.
The guy didn't like completely miss a decimal point or something stupid.
Cause we should move on a little bit from, we've talked about rings,
piston, wall clearance.
I'm talking about piston ring clearance.
Piston ring clearance.
We have not talked about that.
Piston ring clearance is another thing that really bites you.
If you're too tight on your piston wall, ask me a problem.
You're too tight on your piston rings.
That's going to be a big problem.
Now I'm most familiar with 12 valves because I put the most of them together.
I want to say the minimum spec for top ring is around 22,000, but it might even be 20.
I know the max spec for factor 12 is 26,000.
So when you put the ring in and you can either have a ring squaring tool.
When that Todd and I started power driven, he had all these nice ring squaring tools.
I was like, man, people actually buy these cool things.
I've always used a piston upside down.
Well, ring squaring tool is great.
So if you're building a lot of engines, it was a ring squaring tool.
You can get it from summit and places like that.
And I mean, we could even make them on the lathe, but it's very simple.
Better off to just buy one.
They're cheap, but basically you put the ring in, use the squaring tool and it
takes it about an inch down on the bore.
And then you can put a feeler gauge and you're checking the end gap on the ring.
So that's kind of how you check your, your ring gap.
So top ring, as you get more power, there's more heat.
You need more clearance on the top ring.
It's a wear item.
So as your engine gets more mileage, the ring wears, the bore wears, your ring
gap opens up.
I've taken apart stock 12 valves with that ran great.
No blow by that you really noticed or anything on them.
The top ring gap was in the mid 30s, which is huge, way out of common spec, but
you wouldn't have known it because it was just so broken and working so well
that it was that I've also taken engines apart where the top ring was so worn
and gone, the ring gap was like, yes, you know, like a quarter inch, 250,000s.
And it blow by and huffed and there's a huge ring ridge at the top.
So it's eating dirt.
So there is so much that'll do, but you'd be surprised how loose you can make
it in the engine actually.
So don't be afraid of ring gap.
It's not as scary as it sounds.
You're like, oh my gosh, the fire is going to go by there.
And then as far as recommendations, I mean, 12, I'd say if you're over a
thousand horsepower, let's be over 30,000s on the top.
And if you're stock anywhere in that stock range is fine, you know, 24,000s
is plenty for a stock 12 valve.
We generally put the second ring at or a little bit bigger than the top ring.
If you're not running the gapless ring, or even if you are, I still do it bigger.
And then your oil control rings are pretty much, I've never really had to
modify this.
And so if you've opened up the piston wall, let's say you went 10,000s on your
12 valve because it's a thousand horsepower, 12 valve will fear at 10,000s
piston wall, those rings are going to drop in bigger because they factory
precise them where you're not supposed to have to grind them.
Generally we grind them a little bit more, but if you're at 10,000s piston
wall, your top ring is going to drop in over 30,000s and your second ring on
like a Molly power pack, it's going to be in the fifties.
Oh yeah.
You're going to be like, oh my gosh, I got the wrong ring.
And it's like, great.
They designed that in those power pack and an OEM piston, it's not going to
drop in that pig, but there's two trains of thought there.
The second ring has less heat, so technically it doesn't need as much gap.
However, in high RPM engines, if gas gets trapped between the top ring and
the second ring, it can make the top ring flutter and unseat.
And so you lose.
And so I've personally never seen that in our RPM range on these Cummins applications.
Maybe it's our high cylinder pressure, whatever.
So when you run a gapless second ring like a total seal, there's no way that
flows as much as that big gap.
So to me, by that, I argue that you don't need major second ring gap.
However, a lot of the ring manufacturers design that.
And so you just go with what they have.
But so it's kind of like, but you talk to three different engine millers,
they're all totally different theories there.
Without ring orientation, as you put them in the gaps, you don't
win the gaps up top to bottom.
They don't normally that there's instructions and comes with it.
But what I'll do, I mean, this is just.
Does it matter?
No, I just like it.
So I'll put the, the top ring towards the injection pump.
I'll put the middle ring the other way.
So towards the Peter core and then the exhaust span folder, whatever.
Then the oil ring, I'll put that towards like the alternator.
So like 90 degrees out.
Nothing is in line in line straight with a block.
Nothing's perpendicular to the block.
They're all like, diagonals, but you got one across, one across,
and then a 45 or 90.
And I've pulled apart enough engines.
So the rings do rotate.
Yeah, they didn't move 100%.
So the idea for me is just like that first fire won't have a straight
shot where something can cause a problem, probably.
So it's not as critical as people think it is because they do move.
But, you know, they do have instructions on to do that.
So I always do now.
Go just you talk about ring gap on a 12 valve ring gap on a common rail.
I don't think it's like anything.
Like if you plan on beating the crap out of it, this is like,
something you just want to be able to sled pull where you're doing a long
pulls, you're doing fuel only stuff.
I mean, fuel only, I mean, I'm up at 2,400 degrees, like, you know,
there's some heat in those pistons.
If I was like doing my drag racing stuff where it's five, six.
So drag racing fuel only 2,400 degrees, drag racing with nitrous, making
four more hundred horsepower, 1,700 degrees, like depending on what you're
doing with the engine, it's going to change what you should do with your rings.
But just as a reference, like kind of your same thing you said with 12
valve, like my tow trucks at like 26, I believe on the top, that's fine.
That's on the looser side.
Like I don't need that for a tow truck, but it makes good power.
And I like to be able to, I mean, I, I pull grades for a good power for
quite a long time.
And so I like just the, the peace of mind that it's not going to
bud or anything.
Um, if you're like closer to a stock air, like 500, 600 horsepower, 22, 24
would be just fine.
And then on the big stuff that kind of depends on, again, your
piston wall, because you have smaller piston wall, that means you have
less, um, exposed ring as well.
And so it's going to, even at the same temperatures, it's going to swell less.
And so let's just say you're doing like a, I think if you had like a
engine that you want to beat the crap out of and you just don't want to
worry about scuffing, nine to 10,000 should be just fine for piston to wall
for basically a lot of the engines, unless you have a forge piston.
Um, and for that, I would be in that 30, 32,000 ring gap range and on the
top, on the top, middle, same thing, like top plus five.
Um, one thing I have, you're a fan of making the second one a little
bigger than that.
It really doesn't give you a choice.
So I just kind of, that's what I do.
Now, um, that being said, I have had it where, and I don't know why I bought
a set of standard rings for my standard board engine and they've tried to drop
in at like 48, I'm like, I'm not doing this.
Like I'm not going to do 48.
Like I'm, I'm all about it, but not 48.
Uh, and so I bought another set of rings, like same story, 40, 45, 48.
And I'm like, well, so I bought 20 overrings and you have to grind the
everloving crap out of them.
But with that, I was able to just set the middle wherever I wanted.
Those early days.
So I did end up grinding it, but I had no ill effects of that.
So if you do get like clearances, like you, somehow your engines will
loosen you want or whatever.
And you, you don't like that you're going to drop these rings in at 35.
You can buy a 20 over ring set.
You have to do a lot of grinding.
Um, but for that, like I've always just on most of my motors, I'll put some
early ones, I guess I have always just made the middle ring, 5,000 bigger.
It works.
I haven't like seen a need to play around with it.
Um, and then on the bottom ring, it's a good idea to just double check it and
make sure I always go for a 10,000 oil control ring.
Yep.
Pull that little spring ring out of it.
Just drop it in the bore really quick.
Only time I've ever had to touch them as either AI put 20 over
rings in it to where, yeah, they weren't going to clear, or I actually had a set
ship with a defective ring where I had like 70,000 of clearance.
Generally they're all in that 10, 15, 20, thou range, but on a
stockish motor, I'd make them 10 on a bigger motor.
I'll do 15.
I don't think it matters, but it makes me feel a little bit safer.
Um, but you don't really have to grind them.
They'll drop in there, but you've, but you've ran oil control rings as tight
as 10,000 on the bottom and 15.
I've had some as loose as let's say like 22,000.
You get bigger than that.
You aren't going to control oil as well.
And, and when I said it was like pressure, I said it was 80,000.
I think the defective one I got was like probably 120,000.
Like you drop it in the morning like, Oh, well, that was way, way wrong.
And so we did the most logical thing we could think of.
And we just put in one of the stock oil control rings and it was the Junker.
That's the motor you just needed.
Congrats.
Just speak of Junker.
The very first motor I put together, someone set me some rings like cause
they were like trying to almost like help me, you know, as this poor guy on the
forums and somebody might have been Zach Hamilton sent me some rings.
He's like, Hey, but, uh, one of the oil control rings is missing.
So you're going to have to get your own.
So I had a set of, of six.
And so I was like, I was like, I was like, I can't, I can't use.
I was like, I can't reuse my old ring.
And so I looked and I think there's like some sealed power rings from like
auto zone, and it was like $38 for one ring.
And I was like, it's like, or set of rings, but I was going to use one.
Maybe I was like, man, so I took that.
I took those used rings out.
Well, I didn't know how to like, and I broke, I broke one.
So now I needed two when I was like trying to install them.
And so I ended up putting one set of sealed power oil ring, one used oil ring.
And then the other four were new and they were like, how to use the oil ring.
So it's been down that road and you ran fine with that.
Probably the same ring.
That's awesome.
But we did have a question.
Somebody's asking, have we used total seal rings recently?
Total seal released the total seals of performance ring manufacturer in Arizona.
They make great rings, they come for all types of race applications.
Typical race rings are rectangular.
I mean, if you looked at the side profile, the rings wider than it is
thicker and they're kind of rectangular and they might have a
barrel shape on the face that goes towards the cylinder wall or a napier
with like a taper, things like that.
Total seal recently made a keystone ring.
So the side profile looks like a keystone, which is what a lot of these
factory style rings are.
And they have kind of like two different options.
They have one that comes with a gapless second and one that comes
like a conventional second.
And they're a good ring, very similar to like what you'd get.
The Cummins factory rings are really good.
The Mali rings seem to be very high quality as well.
You can kind of tell when you're grinding them, they're good, hard material.
There's so many aftermarket rings, I couldn't even go over all of the other
brands from Interstate McBee and PAI and.
Yeah.
You know, UEM.
But we in the total seal, they do have that gapless second ring.
And we found when you use that upgraded second ring, the oil stays clean longer
and there is a little bit less blow by the one caution I'll have.
Years ago, Todd had an engine that we'd built that we were too tight
and it had butted the rings.
Yes.
And the second ring caught all of that combustion pressure and it ripped
the aluminum ring groove off and actually crashed the middle ring into the
oil ring and shed some of the oil ring down halfway into the crank case.
And so if you catch too much combustion pressure with that second
ring, that is not the steel reinforced strong part of a cast piston.
You can break that.
And so I'm a little concerned.
Let's say I was building a 2000 horsepower engine with cast pistons
because Myra tells us their factory race pistons.
I do question if that gapless second in the case where the top ring flutters
or loses tension or whatever, will it catch too much of that combustion
and potentially make the piston fail.
But that's just an unknown that we haven't tested.
We have had that failure with a conventional gap second ring
when there was a top ring budding scuffing problem.
Let's talk quickly about, you know, we kind of got where now the pistons are in,
rings are set.
Let's talk about like, I mean, lock tight.
We got to put, we put lots of bolts in these engines, put gear cases on.
We're, you know, seals for the crank seals on all that kind of stuff.
The the oil, galley, passage, rifle, those are thing plugs.
Like what do you just put those in dry?
Like what do we do on this?
We do lots of different things.
So yeah, there's three lock tight or four lock tights.
I believe if you're building an engine and to do it correctly, you need them.
You need a red, like a two seventy one is like you're kind of more your standard
grade two seventy two.
If you never want to mess with that bolt again, then a blue lock tight,
which I actually don't know the number on a blue lock tight.
And then you got green lock.
So red is like high temp, high strength lock tight blues, like your mild grade
lock tight, those are thread lockers.
Then you have your green, which is like your six twenty or your six eighty six
eighties, like your more fast set, low temperature, six twenties, like slower
setting, which can be nice, but it's higher temperature.
I think for an engine billy, the one of those would be just fine.
And then you have your five forty five.
And that's a sleeve retainer.
That's where like knocking your oil galley plugs in.
So definitely have one of those green ones.
And then you have your five forty five, which is like a purple lock tight,
which is a thread sealant.
And that's what we'd put on any tapered fitting, like a eighth inch
amputee plug on the side of the block or like your, your coolant plugs on the head
and stuff.
If it's a tapered fitting that doesn't use an O-ring by forty five.
And so for, for me, it feels like a stockish motor.
That's not going to see a lot of force, a lot of RPM.
I would use blue mostly throughout all the hardware.
To me, any bolt that's like less than an inch, that you don't have a lot of room
for like shock absorption.
And so you really should be lock tighting it that way.
It doesn't want to come out.
It's just to help help prevent it from coming out.
If it is a call it up eight hundred horsepower motor or above, I would just
red lock tight the whole thing because you start getting like five thousand
RPM, things want to come loose, stuff vibrates and shakes.
I remember like my, my OG, the, the shorties engine, which that thing was
an absolute champion.
It's like the thousand horse truck that everyone wished they had because the
only issues I ever had as I snapped input shafts and I bolts rattled
loose, I had to take the front cover off and retighten up all the bolts in the
front case because I was an idiot and torqued everything to spec with blue
lock tight because like the blue failed on you on a thousand horse engine.
And the, I had a coolant leaked because the alternator bracket.
That's also the coolant, like the AC bracket that also seals the bottom lower
neck, it came loose and started to drip.
And so I had to, you know, take everything apart and retight, retighten
the bolts and everything, put it back together.
Like it was such a legendary engine that never had any issues.
It had 10,000 piston wall and 32,000 top ring gap.
Never, it didn't like have like any blow by.
It didn't have like a, the catch can did not drain itself.
So every time I do an oil change, I would drain it and I had like maybe two
tablespoons of oil in it every time.
I'm like ridiculous.
Like I love that engine.
It was like, like say the thousand horse engine, everyone wished they had
because it just never had issues.
And yeah, that's where I learned like, yep, torque spec.
The factory torque spec is a little low.
I try to go up to like most of those bolts are like 18.
I'll do like 20, 22.
And then if you're talking about 5,000 RPM red, that's be real.
Like you can get red out.
Like people think like, oh my gosh, red's permanent.
You're never going to get that out again.
It comes out.
It's easy.
It's they'll come out, but basically over 800 horse recommend you go to red.
So like all those gear case bolts on the front.
Oil pump bolts, the cam bolts, oil pump bolts are long enough.
I don't actually usually you're skipping.
No, I do hit those.
I hit those with blue though.
I don't know why.
I just don't feel like that's as necessary to me.
It's the bolts that are shorter.
Like if it's M8 bolt, less than an inch, it doesn't like say it doesn't have
the ability to do shock absorber.
Those are the ones that seem to have issues.
The one that hold the case to the block, those are really short.
Those have issues like say the AC bracket, they're a thick bolt.
They're a little longer, but because they're thicker, you need more length
to be able to help those have issues.
So oil, galley plugs.
Obviously we'll put the green Loctite on them, knock them in because that's
designed to retain those, those seals and sleeves and stuff like that.
What about the freeze plugs?
You just tap factory freeze plugs in.
I have never actually, I have one time used factory freeze plugs and it bit me.
So I just put billet ones.
So a lot of people think that billet freeze plugs are gimmick or a dress up
item and they do look nice.
They've been made look nice.
They are 100% necessary on a elevated power level Cummins because you're
going to turn more RPM.
It's going to make cool and pressure.
The one that bit me was, it was a, it was actually a customer's bill that we
built a, this was way back in the day, um, but it was like a tow truck.
It was not even a big power.
And then we were going to dyno tune it for him.
We put it on the dyno and it wasn't like it was wet still.
I mean, this engine had been built for weeks and put on the dyno, did a
couple of passes and it blew the rear one out.
And I'm like, I know I use green.
Like I'm pretty, I'm pretty, I love my green lock type.
And so I'm like, well, crap.
So we ended up just replacing them all in frame with billet ones just because I
didn't want to have that issue.
And it's like, that was a sucky issue to have on the dyno.
That'd be an even worse issue to have going down the road, especially
towing something.
So yeah, since then I'd, I've never used a factory freeze plug.
Um, just because I mean, even like you said, oh, my factory ones worked for
the first 200,000 miles after 200,000 miles, they're pretty stuck in there.
Like you put a brand new one in there and they probably got a hundred
thousand miles of stock power level usage and maybe because somebody had
their new truck and like, oh man, I don't want to, I don't want to break
in this new truck heart.
I'm going to treat it, you know, yeah.
And so, and like the factory one also had a really clean, that's another thing too
is like even our billet freeze plugs, we have no ring in there.
You have way better sealing ability, but people will just throw them in dry.
I'm like, yeah, the, the freeze plug is a great design.
The factory bore you're putting it into probably is a little rusty and
corroded and probably not as great of a sealing surface that you, as you'd want.
So I always just RTV them as well.
That way you just know if there's any like rust pitting or anything in that
surface, in the block surface where it's going to, um, possibly cause a leak,
just glue it up.
The only time I don't glue them is on our new blocks because again, you're back
through a factory, nice smooth finish, no pitting, like just run it in there
with a little bit of oil and that's been always been great for me.
So kind of handlock tight stuff.
We didn't talk at all about assembly lube.
We've used many over the years.
The one thing I feel like is worth buying.
I like that, that Joe Gibbs, that driven assembly grease for cams and tappets.
Yeah, flat tappets.
Flat tappet.
That seems like a really nice product.
Um, I mean, I've used regular.
We built a lot engines.
I don't think we've ever wiped a cam.
We've done was that one with Weston.
I think I don't remember what happened there.
There was a steel cam in a factory block and it was already ran another engine.
So it might've kind of had a little rough surface finish.
I don't know.
Park raising.
Nice.
That was your engine.
That wasn't supposed to go.
Anyway, it's supposed to be right now.
Oh, there's another one.
I broke the failed.
We're up to 10 now.
We were the podcast or like, well, I was like, well, you probably got more engines
for yourself than anyone else.
He's like, it's not that many.
It's like five, six, seven.
Eight, nine.
But yeah, that one of yours that cracked too.
Oh, yeah.
That was that was yours.
The main engine that blew up.
You built that because if we were able to dynamite the main engine.
You've got a lot of.
Oh, that one that likes and pistons in the stands.
That was my name too.
I built the main engine.
Nothing's a champ.
It's right behind us.
But yeah, like they say assembly grease is definitely.
I like it a lot.
We have like the Joe Gibbs talking about driven.
There's also another one we use for the Colub.
Yep.
Like I think it's an SL 3331 or whatever.
It's black and it works really well.
It's got Molly in there and it's nice because it, you know, if you have dirty hands,
then it hides your dirt from your hands.
That's not the reason we use it.
But it is nice officially.
Anyway, there's a lithium, a white, a white engine assembly grease,
which I've seen different people use.
And it's, we've used it before and we haven't any negative.
I used it when I put this engine together and I pulled the oil pump out the other day to inspect it
and it was like almost kind of set up in there and it's only been in there for like,
that's like chocolate in my mind.
Like six months.
I don't really like it.
I've never had a problem from it, but after seeing that,
I'm kind of done with the whole white lightning.
You know, you go with the driven and the whatever the black stuff is.
We use it at a stay loop.
Stay loop.
Yeah, those, those are good.
I mean, I don't think you have to get exotic.
Those are just a good assembly grease.
I've used the, the red, I don't know if it's from Lucas.
Oh, the Lucas is kind of like, like a oil colored kind of a gold color,
but we've also used that red.
I don't know if it's Permatex brand.
The red snot.
Yeah, the red snot.
It's Permatex.
I'm pretty sure.
Permatex.
I've used that.
So we've used lots of stuff and had no issues.
We, a lot of times, I mean, I'm trying to think I use like engine oil when I'm doing
some stuff like lubing up.
I mean, you can use that, but if you're going to start the engine right away,
you can, if it's going to maybe sip a little bit, like the assembly,
Lou better just for doing the cylinder walls though.
Come and spec, I think you, you have a different opinion about this than I do,
but come and spec for like lubing up the piston rings is to dunk them in a bucket of oil.
And so engine oil, I don't do that.
I use a squirter can, but I try to make it so where you can't tell what I did.
It could have followed the factory spec.
Like I put a couple of shots in there, spin them around and make sure there's nice oil.
That's what I do now.
I use, I use oil can.
I'll shoot a couple of shots in the gap of the ring.
Yep.
And then just sit there and spin, spin, spin oil coat on.
Cause like when it's dry, you can feel like there's like some scratching.
And then once it's all fully lubed, you can just feel it's like everything glides.
Then we're good.
That's what I do.
Do that.
I do that.
And I make sure I don't like dunking an oil.
So there's people here that really wanted to know like startup techniques break in and we
should get on that before we lose all of our time in this podcast.
So there's like so much to talk about with Bill again.
I didn't realize it unless we're going to do a part two, but why not?
Do you think we should do a part two guys?
Comment below psych too late.
Well, if we're not going to cover like breaking and stuff, let's just finish a
little bit on the assembly then.
We had a couple of minutes left.
We, we still got bearings.
Some people are scared of age bearings.
Like, Oh, age bearings don't belong on the street.
Well, you, we should talk about what we lube.
We're still on talking about grease.
Sorry about that.
So camshaft, all the journals, all the lobes, you don't like go crazy.
I don't use gloves.
You say you don't go crazy.
I don't use gloves for basically anything.
I'll throw a pair of gloves on it.
We can like coat that thing.
When you're doing a camp, camp ain't going to dry.
So cut the camp.
Okay.
You can just dunk it in a bucket of loob.
Give yourself a ballot.
Like if you have your own drum of the staleo.
There you go.
That's done.
Definitely the left here is the bore.
I lift the face and the, and the whole, the pocket, the pocket.
Yep. The whole thing.
I actually don't lube the pocket as much because I do the pushrod, but either way,
it's good idea to do both that way.
If you forget one, it's still looped.
You want to loop down there.
So that's kind of your cam stuff.
Make sure everything's looped up there.
Bearings, we put it on the side of the crank side or the, yeah,
the crank side of the bearings.
You don't put it between the bearing and the rod or the bearing in the main cap.
I'm actually, as you're talking, I'm thinking of so many more things to cover.
Maybe you should go to number two.
We should go to cap two.
What do we need to cover to just finish?
It's really, we got to talk about where you put to you.
Yeah. The whole cylinder head assembly.
We haven't even touched the cylinder head yet.
Touch that.
Haven't touched break it.
Haven't touched bearing choices.
Wow.
Retorques.
There's so much about engine.
You don't even realize.
All right, guys.
I'm going to call it.
We're going to have to do next week.
We're not going to make you wait for we're going to do two in a row.
So this week will be what got done here.
The next week, we're going to just continue right on from where we left off
because we got, there's, there's more information that we're going to
for the next 10 minutes.
So anyways, that's going to end up this episode right here.
That worked on next week and we'll come back.
And as always, like, subscribe, give us comments.
A lot of our ideas come from you guys.
So let us know what you want us to talk about and we'll do our best.
Thanks.
See you next time on the pageant podcast.
About this episode
The hosts dig into the practical side of building Cummins engines the right way, starting with inspection and cleaning, then moving into measuring clearances, ring gap, piston-to-wall fit, and bearing setup. They share a lot of hands-on tips, like chasing threads, cleaning oil passages, checking cam bearing alignment, and using spreadsheets to track measurements. The discussion also covers ring orientation, oil clearance choices for street versus race builds, and how different parts and clearances affect durability and power.
If you have ever cracked open an engine block and wondered whether you are missing something the shop guys never talk about, this episode is for you. Todd, Will, and Myer break down the real hands-on engine building process, step by step, using their Myers UCC build as the backdrop for a conversation that covers everything from the stuff you check before you turn a wrench to the stuff that will bite you if you skip it.
The episode kicks off with oil galley plug inspection, what the guys call the oil rail, oil rifle, or oil passage depending on who is talking, and why making sure every one of those plugs is seated before assembly is a non-negotiable. They get into cleaning procedures using an engine bore brush kit to pull out machining particles and metal flakes from the cylinder bores and oil passages before anything goes back together.
Bearing clearances get a solid breakdown here. The guys walk through main bearings and rod bearings on a Cummins engine, explain why the oil holes in the bearings do not line up the way you might expect, and talk through what proper clearance looks like for street builds versus high RPM race applications. They also hit a detail that trips up a lot of first-time builders: rod caps are matched to their specific rod during the machining process, and swapping caps between rods will cost you roundness and likely an engine.
Cylinder wall prep takes up a good chunk of the conversation too. The guys reference using the Total Seal ring break-in compound to verify cleanliness, where green means the wall is ready and brown means you are not done yet. From there the discussion moves into piston ring gap, how they set the second ring at or slightly larger than the top ring, ring orientation during installation, and their experience running Total Seal gapless second rings at higher horsepower levels where piston land strength starts to become a real concern.
The back half of the episode covers assembly lube, specifically the Joe Gibbs Driven line and other black assembly greases the guys have had good results with, where to apply it and where not to, and the proper way to lube a camshaft, lifters, and cam lobes before the engine goes together. The cylinder head side of the build runs long and gets pushed to next week, so consider this Part 1 of a two-part deep look at what it actually takes to build a diesel engine the right way.
Subscribe on YouTube to catch Part 2 the moment it drops, and if you are listening on Spotify or Apple Podcasts, follow the show so you never miss an episode.
Everything the guys talked about in this episode, rings, bearings, assembly products, all of it is the kind of stuff you can find at PowerDriven.com. If you are building an engine, start there.
