2017 X6 50i coolant leak

[Cozy2017]

COOLANT LEAK

2017 BMW X6 50i
Does anybody have any type of knowledge about this coolant leak ? This is my first v8 and I didn’t know there was 2 coolant tanks and I let the turbo tank get dry smh . Cant see leak from up top . Afraid it’s leaking from transmission , BMW quoted me $5630 smh[ATTACH]undefined[/ATTACH]

[jfandl]

Take your car to an independent BMW shop. There are often much more affordable solutions than a dealer can offer. The dealer generally sticks with BMW only parts instead of two solutions. For example, my local BMW stealer wanted 2,100 to swap out a leaking turbo coolant line. The hose is stainless and rubber. Nothing wrong with the stainless so I bought a new BMW hose for $70 , swapped the rubber section and 45 minutes late, was completely finished. An independent shop could have done the repair for hose + markup plus an hour labor.

[tfunk88]

The first pic isn’t showing for me.

The smaller coolant tank is for the intercooler system. This reduces the temp of the intake air as it heads into the turbo. I don’t think it leaking would go to the areas of your second pic as the lines are all at the front of the engine except for the couple that go to that small reservoir.

I’m guessing your turbo coolant lines or the head coolant return lines are leaking into the V of the engine, then coming out the back where there is a drain hole at the transmission junction. If you take off the engine cover and airbox I bet you’ll see evidence of leaking coolant.

[Chilled]

As per the suggestions in your reddit thread, have a better look at the top of the engine.

[Cozy2017]

UPDATE: The mechanic would only work on the car if I paid him to take apart the turbo and have him replace all the hoses up there than if that wouldn’t work he would drop the transmission and do it that way . So I refilled the turbo coolant tank and the leaking stop . Haven’t leaked since it’s been 2weeks ish and steady coolant levels in both tanks . Kind of lost for words , could it have just been leaking due to high pressure build up from the turbo running to hot and coming out at its weakest point ?

[Chilled]

The coolant caps can open up if the pressure inside gets to high. More often then not, on these things the reason for the high pressure is that there is a leak, air has gotten inside the loop and is now expanding forcing the cap to open up to relive the pressure.


Try the bleeding procedure.

Leave the coolant expansion tank sealing cap open during the bleeding procedure.

Top coolant up to the upper edge of the expansion tank. Coolant level may not drop further! No drop in coolant for approx. 1 minute.
Connect battery charger.
Switch the ignition on.
Set heating to maximum temperature. Press Automatic button. Then set the blower to the lowest speed.
Press accelerator pedal for 15 seconds to floor. Engine must not be started.
The bleeding procedure is started when the accelerator pedal is pressed and takes approx. 12 minutes.
Refill expansion tank up to top edge immediately after drawing off until empty.
Adjust expansion tank to maximum level at end of bleeding procedure.
Check cooling system for leaks.
Close expansion tank.
If the cooling system bleeding has to be carried out again, allow DME to drop completely (let the ignition key be removed for approx. 3 min), then repeat from point 5.

[tfunk88]

Originally Posted by Chilled

The coolant caps can open up if the pressure inside gets to high. More often then not, on these things the reason for the high pressure is that there is a leak, air has gotten inside the loop and is now expanding forcing the cap to open up to relive the pressure.


Try the bleeding procedure.

Leave the coolant expansion tank sealing cap open during the bleeding procedure.

Top coolant up to the upper edge of the expansion tank. Coolant level may not drop further! No drop in coolant for approx. 1 minute.
Connect battery charger.
Switch the ignition on.
Set heating to maximum temperature. Press Automatic button. Then set the blower to the lowest speed.
Press accelerator pedal for 15 seconds to floor. Engine must not be started.
The bleeding procedure is started when the accelerator pedal is pressed and takes approx. 12 minutes.
Refill expansion tank up to top edge immediately after drawing off until empty.
Adjust expansion tank to maximum level at end of bleeding procedure.
Check cooling system for leaks.
Close expansion tank.
If the cooling system bleeding has to be carried out again, allow DME to drop completely (let the ignition key be removed for approx. 3 min), then repeat from point 5.

This procedure is for the 35i, which has an electronic water pump. The 50i has a mechanically driven water pump.

[tfunk88]

Originally Posted by Cozy2017

UPDATE: The mechanic would only work on the car if I paid him to take apart the turbo and have him replace all the hoses up there than if that wouldn’t work he would drop the transmission and do it that way . So I refilled the turbo coolant tank and the leaking stop . Haven’t leaked since it’s been 2weeks ish and steady coolant levels in both tanks . Kind of lost for words , could it have just been leaking due to high pressure build up from the turbo running to hot and coming out at its weakest point ?

Just to clarify…there is NOT a separate “turbo coolant tank”. The coolant that runs through the turbos is the same coolant that runs through the rest of the engine. The “tank” for this system is the large reservoir on the left side of the engine bay. There is a smaller auxiliary pump that helps to send coolant to the turbos, but it uses that same engine coolant. The small “tank” on the right side of the engine bay is for the coolant that runs through the intercoolers, which also has its own separate electric pump.

So if your small tank ran dry, that is coolant for the intercoolers, not the turbos.

[Chilled]

Originally Posted by tfunk88

This procedure is for the 35i, which has an electronic water pump. The 50i has a mechanically driven water pump.

Are you sure, maybe only the ///Ms get an electric pump for the charge coolers. As in i've done the process and could def see the charge loop try and bleed itself.

*Edit* I'm assuming its the charge cooler tank that was leaking as most of the coolant looks to be on the left side of the engine.

[tfunk88]

Originally Posted by Chilled

Are you sure, maybe only the ///Ms get an electric pump for the charge coolers.

*Edit* I'm assuming is the charge cooler tank that was leaking as most of the coolant looks to be on the left side of the engine.

Yep, the 50i has 3…count ‘em, THREE…water pumps lol

It has the main mechanical pump. It also has a small pump that is part of that same circuit, mainly for circulating coolant through the turbos after the engine is shut off. And then there is a third water pump that is strictly for the intercoolers.

Also, while the process may have started the intercooler pump, there’s not necessarily a need to bleed the intercooler system running the pump as there is with the 35i main cooling system. If you fill it slowly it’ll mostly bleed itself. Then you can just drive the car and add a little bit later.

The main engine coolant must be vacuum filled or else there 100% will be air pockets.

[Chilled]

Welp, ill take your word on it.

I'm not game enough to spend the next 3mth pulling all the hoses, accidently breaking all the hoses, swearing at the hoses, forgetting how to put this thing back together and then begging whilst paying through the nose to have someone put this thing back together, just to verify.

[tfunk88]

Originally Posted by Chilled

Welp, ill take your word on it.

I'm not game enough to spend the next 3mth pulling all the hoses, accidently breaking all the hoses, swearing at the hoses, forgetting how to put this thing back together and then begging whilst paying through the nose to have someone put this thing back together, just to verify.

Ooooh did I miss something? Did that happen to someone?

When I did my valve cover gaskets and water pump back in Oct/Nov I got WAY more familiar with the cooling system…and other systems…than I wanted to 😂

[Chilled]

Originally Posted by tfunk88

Ooooh did I miss something? Did that happen to someone?

When I did my valve cover gaskets and water pump back in Oct/Nov I got WAY more familiar with the cooling system…and other systems…than I wanted to ��

Nah, a stab at BMW and the amount of stuff they shoved in the engine bay. When you open the bonnet, if you squint really, really hard, if you're lucky, you may* see an engine. Was thinking about your thread and was thinking about myself and was like hmmm, nah half way through i would of pulled out the sawzall and then gave up.

I'm still impressed you remembered how all that went back together given how long it took.


*Edit* Granted i think I'm slightly loosing my sanity after been stuck in a meeting where the technical leads say they dont know what to do/ how to proceed forward because our setup doea not look like the youtube vid he was taught with and they're team is not sure how to proceed.

[tfunk88]

Originally Posted by Chilled

Nah, a stab at BMW and the amount of stuff they shoved in the engine bay. When you open the bonnet, if you squint really, really hard, if you're lucky, you may* see an engine. Was thinking about your thread and was thinking about myself and was like hmmm, nah half way through i would of pulled out the sawzall and then gave up.

I'm still impressed you remembered how all that went back together given how long it took.

Ha ha the worst part was there were definitely a few times when I was putting it back together that I thought “Umm, did I really NOT take a pic of this before I took it apart? You IDIOT!” Thought I had snapped a lot of pics but apparently I fell well short of my “100% documentation” goal😂

Fortunately for the most part it “kinda” made sense. Only had to reroute things a couple times. At least that’s my story and I’m sticking to it…

And next time I do it I’ll only do it when I have a week or so to dedicate to it. Not this “a few hours here and there” BS 🤦‍♂️

[tfunk88]

Originally Posted by Chilled

*Edit* Granted i think I'm slightly loosing my sanity after been stuck in a meeting where the technical leads say they dont know what to do/ how to proceed forward because our setup doea not look like the youtube vid he was taught with and they're team is not sure how to proceed.

Haaaaaahahaha sounds like your technical leads are very adaptable and at the top of their game 😂