2017 BMW M240i Coolant Leaks

Hi, it's Mark Bossert. I'm here with Bernie Pawlik, Pawlik Automotive in Vancouver, BC, Canada.

Vancouver's best auto service experience. And we're talking cars. How are you doing,

Bernie? Doing very well. Well, this morning, our guest is a 2017 BMW M240i. They love their

long names, BMW. What was going on with this vehicle? We can add XDrive onto the end

of that, too, just to make the name even longer. This vehicle came in with a coolant leak. Also

needed rear brakes, but we'll talk about that another time. But yeah, it came in with a coolant

leak. So we did our diagnosis, which consists of a pressure test to start. Found some leakage

from the water pump and areas in behind the water pump. These are often buried, so

things need to be removed to find out where the actual leaks are coming from.

But at the very least, we knew it needed a water pump.

So this being a smaller BMW, is this still like what motor is running in this?

It's got a six cylinder twin turbo. Inline. Inline, yeah. I say traditional BMW. So there's

our beautiful little convertible sports car. Very nice little machine. There's the view

of the engine crammed into that little engine compartment. This view here actually shows

part of the process. We remove the intake manifold to access the rest of the cooling

system because to get the water pump out, there are bolts and items underneath the

intake manifold. So we start with that, but there's a whole bunch of cooling system components

underneath the intake manifold and with those arrows all point out a few. So the red arrow

just points to the radiator hose that goes from the radiator to the engine. There's

a plastic piece that yellow and red hose attached to. There's a temperature sensor

in there. And the red arrow I put there because that's basically a very common

clip that they use on not just BMWs, a lot of cars, but it's basically a snap

together clip. So that's a plastic fitting, snaps onto the housing. There's a rubber o-ring

in there. Those things can leak the moment you touch them or move them. They deteriorate

over time. So we replace that. The yellow arrow I'm just pointing to the clamp on

that. That's a pinch clamp on a traditional rubber hose. And those don't need to be

replaced because they tend to last. They're very reliable. Why they don't use

them more. The reason they don't use them more often is because it's way

easier to assemble stuff with snap together clamps. The blue arrow points

to an item called the coolant thermal management unit. It's a very fancy name

for a thermostat. And that piece we also replaced in the process because we had

to remove components from that. And the moment you touch anything on these,

usually you end up with a coolant leak. So you didn't want to have the customer

come back with a coolant leak coming from somewhere else. Now there's the

front view of the engine. This is where the water pump is located. That

red arrow actually points to the water pump. And unlike a lot of BMW engines

which use an electric water pump, which has the thermal management unit beside

the water pump of the thermostat. This one uses a mechanical water pump driven

by the fan, which is a little different than BMWs used for quite a while. In

order to remove the pump, you got to move this and this. Yeah, that's right.

So the item on the right where you're moving your mouse pointer, that's

the air conditioning compressor. We don't have to discharge the air

conditioning, but it just needs to be unbolted from that housing. And the

alternator also needs to be removed. Again, they're not a huge, you know,

they're a couple of bolts, but they're all things that you need to do to

remove these pieces. So all of those have to come off. And then once the

water pump is unbolted from the block, it comes off that thermal

management unit. There's a coupler that connects them. That piece broke

just because it's all brittle plastic. And that's only sold with a

thermal management unit. And it sounds like a country and Western song.

It's like, you know, this broke and that broke. It's right. My dog

died. Your dog died. Yeah, exactly. Yeah. So this is a view of the

thermal management unit. You can see that the coolant hose that was

there on the right, the radiator hose is off. And there's a few

pieces in there. We replaced all of those items, except that hose

that had the yellow arrow to it. Because again, I've mentioned

those clamps are very durable. And it's rubber, not plastic.

That's rubber. Yeah, exactly. So anything that plastic is

really just kind of asking for trouble. So this is that

thermal management unit. Again, a fancy name for thermostat and

very expensive. So we're looking sort of the inside where the

coolant flows in from the water pump. And this unit will divert

coolant into the engine or heating system or wherever it

decides to go, depending on where the most effective cooling and

most effective energy usage. This allows the engine to

warm up properly when you first start it when it's cold. It

prevents it from overheating when you're driving hard or

whatever, etc.

Exactly. Yeah. And that's kind of key. If you get into a really

old car, like say 30 years old, and you hop in, you turn it on,

especially on a cold day, it'll take a while for the heat to

get in the cabin. A car like this, you have some warmth

trickling in on a super cold day, even in a minute. So yeah,

it makes a big difference. And here we have this is the water

pump with the housing. And so that piece that we're

looking at sort of in the bottom left, it has a big

black seal around it. If we look closer at that seal, you can

see it's already deteriorated and kind of disintegrating. And so

this was leaking a bit just kind of happens over time. So this is

metal, it's not plastic, like we complain about how it tends to

wear out. But again, the seals tend to go so. So did you just

replace the seal on this? Or did you have to put in a whole

new water? No, the water pump comes complete with the

housing. You can actually buy a water pump without the

housing, but BMW doesn't sell it that way. There's after

market pieces, you can see the water pump doesn't bolt from the

housing. And it was leaking, but not as severe as the amount of

leakage was coming out. So we knew we had two leaks on this

vehicle. So there was a leak in here, where I'm moving,

roughly in there or up in here, the other end, and then as

well here. Yeah, exactly. Yeah. So then you replace

everything. Yeah, replace everything. What's this?

This is a plastic coupler that goes between that metal water

pump housing and that thermal management unit. And of course,

the process of taking it apart, we're very gentle and careful

as we could be. But the piece in the plastic on the top, this

little nipple that sort of sticks up, that piece snapped off, it

just kind of happens when you try to gently move things out

sometimes. Again, plastic, old and brittle. And that piece,

unfortunately, is not sold separately. You have to buy

that whole thermal management unit. I'm not going to say how

much it was. It was a lot of money. It comes complete

with that. So once you've repaired all that stuff, put

everything back together again, how was the vehicle running?

Perfect. Runs awesome. No leaks. When everything is done

complete, so there won't be any, oh, you know, six months or a

year that's like, oh, it's leaking from there. We got to pull

the intake manifold back off to fix something. It's done

complete and should be good for another eight years or

hopefully longer. It's a good car. It should last for a

long time. It should have lots of life left in it. If

you're having issues with coolant leaks, the people to

see in Vancouver are Pawlik Automotive. You can

reach them online at pawlikautomotive.com or you can

call them to book your appointment. You can call them

and talk to someone too at 604-327-7112. You have to

book ahead. They're always busy. Pawlik Automotive in

Vancouver, BC, Canada. Thanks so much for watching and

listening. Thanks, Bernie.

Thank you, Mark. Thanks for watching.

BMW M240I

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