[Tr4ckD4ys]

Apologies for cross-post but the X7 community is more concerned with software problems of the new iD8.5 rather than good ole mechanical problems.

2022 X7 M50i Owner:

Since I’ve had the vehicle (29K miles), I have had the “Low Coolant” Warning come on twice. Both times occurred in cold winter/January and both times I topped it off with a minimal amount (about 100-200ml / 8-10oz maybe). The first time was at about 14k miles and exactly about 15k miles later the second time.

I do see some minimal crystallized crust around the coolant expansion tank cap. It is the tank on the right side of the N63 engine that goes low, the one in the center front of it stays super level.

The service advisor said the tank on the right is the one for the turbo cooling. He also said that such a minimal amount of coolant use is normal with these engines due to the extreme heat at the turbos.

What is everyone’s thoughts? Drive it and don’t bother, keep topping off when necessary? Or make an appointment and have the dealer chase a potentially super minimal leak that would hardly show up on a pressure test.

[mmm50i]

My car has 29000km (18k miles). A low coolant warning came up at 15k miles. It appeared maybe 3 times in a span of 2 weeks, only in the mornings during a cold start.

When I finally brought it to the dealer, they topped it up and said it was normal. It sounds like I should be expecting this to happen again in due time.

[BlkGS]

I'm gonna disagree that coolant loss is "normal". The cooling system is sealed, hence it's ability to not boil above 212F. That means that the coolant isn't just evaporating/boiling off. It's going somewhere outside of the system.

That said, it may be typical of a poorly tolerances o ring or something like that, but it's not "normal" in that it's designed to do that.

All that said, it may be tough to get the SA to help if they think it's normal. Ask for a technical explanation and not "because the turbos are hot". They won't be able to provide it and then maybe you can use that to convince them to have a mechanic look at it.

[swainbmw]

[QUOTE=BlkGS;30783682]I'm gonna disagree that coolant loss is "normal". The cooling system is sealed, hence it's ability to not boil above 212F. That means that the coolant isn't just evaporating/boiling off. It's going somewhere outside of the system.

That said, it may be typical of a poorly tolerances o ring or something like that, but it's not "normal" in that it's designed to do that.

All that said, it may be tough to get the SA to help if they think it's normal. Ask for a technical explanation and not "because the turbos are hot". They won't be able to provide it and then maybe you can use that to convince them to have a mechanic look at it.

I believe there’s a YouTube video about this . A guy talks about the expansion tanks, and what to do type in that engine number with Coolant loss

[Tr4ckD4ys]

[QUOTE=swainbmw;30783992]

Originally Posted by BlkGS

I'm gonna disagree that coolant loss is "normal". The cooling system is sealed, hence it's ability to not boil above 212F. That means that the coolant isn't just evaporating/boiling off. It's going somewhere outside of the system.

That said, it may be typical of a poorly tolerances o ring or something like that, but it's not "normal" in that it's designed to do that.

All that said, it may be tough to get the SA to help if they think it's normal. Ask for a technical explanation and not "because the turbos are hot". They won't be able to provide it and then maybe you can use that to convince them to have a mechanic look at it.

I believe there’s a YouTube video about this . A guy talks about the expansion tanks, and what to do type in that engine number with Coolant loss

Could you help me find it? I searched for a while and can only find previous-gen N63 related content.

[swainbmw]

Originally Posted by Tr4ckD4ys

Could you help me find it? I searched for a while and can only find previous-gen N63 related content.

I would need to watch again but I believe it’s the bottle

[mmm50i]

Originally Posted by BlkGS

All that said, it may be tough to get the SA to help if they think it's normal. Ask for a technical explanation and not "because the turbos are hot". They won't be able to provide it and then maybe you can use that to convince them to have a mechanic look at it.

I didn't question my SA last time but if it happens again, I'll definitely be questioning him about the coolant loss. It was my first experience, but the OP had it happen 2 times already, both around the same interval. So it's definitely a concern.

[eelnoraa]

some coolant lost definitely NOT unusual. As much as everything is sealed, nothing is perfectly seal, specially the expansion tank. All mine lost a bit in a while. And BMW, in fact all car brands, sell coolants to end user for reason.

Number here matter, 100mL is 3.4oz. A can of coke is 12oz, so 1/3 of a can of coke, this is kind of normal. Now 10oz is approach a can of coke, it is a bit much. so which one it is?

Also, beside some crystallization, which is normal, do you see coolant anywhere under you car? And if you open hood when ICE is running at operation temperature, can you smell coolant?

[slilley]

All of my recent BMWs lost a little coolant as well, starting with a 2016 X3 and more recently a 2020 X1. As a result, I've added a reminder to check them and top-off every 15K miles. The X5 will hit 15K miles this summer, and I'll check it at that time. They've needed anywhere from 0.5 cup to 1.25 cups to bring them up to the minimum levels at that 15K interval. My 2018 GTI just needed a top-off for the first time, but at 60K miles it only needed 0.75 cup - and I was planning on doing a coolant flush soon anyway. I miss the old days when I could do a coolant flush on my BMWs every 30K miles! Now they don't recommend a coolant flush ever - preferring to wait until something like the electric water pump or thermostat fails.

[puckybadger]

Same persistent problem with my 2020 X6 M50i
Decided to move on from it rather than possibly have to deal with a major unwarranted engine issue

[BlkGS]

Originally Posted by eelnoraa

some coolant lost definitely NOT unusual. As much as everything is sealed, nothing is perfectly seal, specially the expansion tank. All mine lost a bit in a while. And BMW, in fact all car brands, sell coolants to end user for reason.

Number here matter, 100mL is 3.4oz. A can of coke is 12oz, so 1/3 of a can of coke, this is kind of normal. Now 10oz is approach a can of coke, it is a bit much. so which one it is?

Also, beside some crystallization, which is normal, do you see coolant anywhere under you car? And if you open hood when ICE is running at operation temperature, can you smell coolant?

Agreed 100%. A little seepage out of the expansion tank is normal, most of the time that's just a hose to a barb connection. A lot of expansion tanks aren't totally sealed either, or have a run off to an overflow tank, etc.

A little coolant over the years, sure. 100mL in a year is higher than I've experienced on America cars, but different brands have their strong and weak points. American cars typically focus a lot on not leaking fluids, whereas German cars appear to prioritize other things.

10oz in under a year on the other hand is kind of a lot, and I'd be looking for the problem. It could be something as simple as a loose hose clamp on the expansion tank. Maybe a pinhole in a hose that only opens up when it gets hot enough. Either way, it's enough to warrant checking into.

[JimVR4]

I think there could be some misinformation here. To my knowledge the center cap is the one that provides coolant to the turbos. I believe this reservoir gets replenished by the main tank which is on the right.

I got the low coolant warning last November - it was intermittant but I bought a jug of coolant from BMW ($65 by the way), and I topped off the fluid, taking 5 plastic cups to fill (estimated at a quart). Yesterday morning I measured again (since I was taking it for service) and it was quite low once again. When I took in my 2021 M50i, they pressure checked (finding no leaks) and topped it off again. So loss of a quart last November and another quart down since then.

I was told this was considered normal but I have a hard time believing that could be true (unless the turbos are actually buring up this coolant). Still it's alarming to be sure.

My M50i is nearly three years old now with about 23K miles and I never had this coolant loss before last November. So I feel it could be a long term problem. I plan to send a letter to BMW to document my findings on what seems like an extreme loss of coolant.