[Joe-BMW33]

Originally Posted by BrocksM550i

Ok. I had the low coolant notification once right before the oil change

Be persistent with the dealer. These cars DO NOT consume coolant. If you get a low coolant message, you have a leak, simple as that. Sometimes techs are lazy and will tell you it's normal. I haven't gotten one low coolant message in two year since they replaced my turbo coolant lines. I complained and it took the line to cleary spew before they diagnosed it.

[Joe-BMW33]

Originally Posted by G30M

question: is there anything one can do to prevent this coolant leak?

Nope, just a poorly designed/engineered product. BMW is famous for expansion tank failures. It is extremely common on the E39, almost the same issue, but on the E39, the neck cracks.

[G30M]

Originally Posted by Joe-BMW33

Nope, just a poorly designed/engineered product. BMW is famous for expansion tank failures. It is extremely common on the E39, almost the same issue, but on the E39, the neck cracks.

what if i replace the tank every x years?

[Joe-BMW33]

Originally Posted by G30M

what if i replace the tank every x years?

Well of course you can do that. I thought you meant is there anything you can do to prevent it. I did the tank in my E39 preventively (and my old E38). All the power to you, if your "blows", you're probably saving yourself from damaging coils and injectors. I'm going to let my warranty take care of it, if and when.

[NGT2]

Originally Posted by Joe-BMW33

I need to figure out where it is! I will do the same and check frequently. I detail my engine frequently, haven't noticed any residue, but then again, I don't even know where this tank it!

No low coolant warnings, so it's probably intact, for now. I have a feeling this will be my first Route 66 claim.

Back right of the engine bay. I’ll send you my video.

[NGT2]

Originally Posted by G30M

question: is there anything one can do to prevent this coolant leak?

I don’t think so. Just be vigilant.

[NGT2]

Originally Posted by Joe-BMW33

Be persistent with the dealer. These cars DO NOT consume coolant. If you get a low coolant message, you have a leak, simple as that. Sometimes techs are lazy and will tell you it's normal. I haven't gotten one low coolant message in two year since they replaced my turbo coolant lines. I complained and it took the line to cleary spew before they diagnosed it.

One of my coworkers is a navy mechanic that used to work on nuclear ships, in the reactor room. She was laughing at the idea that the coolant would just “evaporate” in a closed system.

I was talking to a good friend that is a hardcore Benz loyalist. He has an Indy mechanic he likes. The mechanic told him that it’s no surprise these plastic tanks and rubber hoses fail on these cooling systems. The engines get so hot and plastic is plastic. After so much contraction and expansion, something is bound to fail.

Maybe with 3D printing or something they could manufacture a tank with no seams? That’s all I can think of.

[adhrp]

Originally Posted by NGT2

One of my coworkers is a navy mechanic that used to work on nuclear ships, in the reactor room. She was laughing at the idea that the coolant would just “evaporate” in a closed system.

I was talking to a good friend that is a hardcore Benz loyalist. He has an Indy mechanic he likes. The mechanic told him that it’s no surprise these plastic tanks and rubber hoses fail on these cooling systems. The engines get so hot and plastic is plastic. After so much contraction and expansion, something is bound to fail.

Maybe with 3D printing or something they could manufacture a tank with no seams? That’s all I can think of.

It amazes me that with all the sophisticated engineering that goes into these cars, the tank is still built with seams instead of one seamless unit! Maybe I don't have the knowledge to understand the challenges, but there has to be a significant challenge, right? Otherwise it makes no sense for BMW not to solve this chronic issue using 21st century solutions

[jphcbpa]

Originally Posted by M550Ali

2022 , Lci headligh/taillight combo is super sexy!!!
Congrats drive it in good health & may you & the wife enjoy that monster of an engine!

concur !!!

[Sideways the Seven]

Originally Posted by NGT2

On spark plugs - my SA said it’s not about mileage but done in conjunction with a number of oil changes. I can’t remember how many.

6 oil changes/60K miles.

[NGT2]

Originally Posted by Sideways the Seven

6 oil changes/60K miles.

Makes sense. Previous owner had low miles and I’m averaging over one change per year. So I can see how I’m on oil change number 5 now and the next one will include plugs even though it will be well before 60k miles.

I’m at 38k miles, by the way.

[Joe-BMW33]

Originally Posted by NGT2

Back right of the engine bay. I’ll send you my video.

Cool, yeah, shoot me that when you get a chance.

[G30M]

Originally Posted by NGT2

Makes sense. Previous owner had low miles and I’m averaging over one change per year. So I can see how I’m on oil change number 5 now and the next one will include plugs even though it will be well before 60k miles.

I’m at 38k miles, by the way.

On my m340 the dealer changed spark plugs at the 3rd oil change "per schedule". my free service waa done at 12500 miles. We get one free service here. Our service schedule is oil change every 2 years / 19, 000 miles on all cars inc M3/M5. Crazy or what.

[tsbrown]

Originally Posted by NGT2

Back right of the engine bay. I’ll send you my video.

Is this just the location in the M550? The main and expansion tanks on the 540i are front-right behind the headlight.

I need to inspect mine before the long drive...it would majorly suck to be in the middle of nowhere and have an issue. Last year I arrived after the 1000 mile drive and got the warning, 2nd one in like 4 years. Reset itself the next day but I ended up topping it off anyway.

[HerkHealer]

Originally Posted by tsbrown

Is this just the location in the M550? The main and expansion tanks on the 540i are front-right behind the headlight.

I need to inspect mine before the long drive...it would majorly suck to be in the middle of nowhere and have an issue. Last year I arrived after the 1000 mile drive and got the warning, 2nd one in like 4 years. Reset itself the next day but I ended up topping it off anyway.

The M550 tank is in the right rear section.
The bottom of the tank is pretty damn close to the engine, which gets VERY hot, especially in summer. It's no wonder these plastic tanks are leaking. They need to have a TSB or something to add insulation to the bottom and sides.
This is just bullshit. Hopefully BMW steps up and solves this.

[G30M]

Originally Posted by HerkHealer

The M550 tank is in the right rear section.
The bottom of the tank is pretty damn close to the engine, which gets VERY hot, especially in summer. It's no wonder these plastic tanks are leaking. They need to have a TSB or something to add insulation to the bottom and sides.
This is just bullshit. Hopefully BMW steps up and solves this.

people have made custom printed coolant tank leak catchers for the F90 M5

any ideas if they will fit on the M550?

[tsbrown]

Originally Posted by HerkHealer

The M550 tank is in the right rear section.
The bottom of the tank is pretty damn close to the engine, which gets VERY hot, especially in summer. It's no wonder these plastic tanks are leaking. They need to have a TSB or something to add insulation to the bottom and sides.
This is just bullshit. Hopefully BMW steps up and solves this.

Or a heat shield....it's not like they don't use those in other parts of the car.

[HerkHealer]

Originally Posted by tsbrown

Or a heat shield....it's not like they don't use those in other parts of the car.

My comment of insulation and/or heat shield are the same thing.
It's something they're going to be forced to identify .
Way too may customers with this this in the M550 and M5 with this issue.

[JoeFromPA]

Spark plugs don’t wear out due to number of oil changes.

For those paying out of your own pocket, pay for spark plugs when usage drives it. Which is mileage.

[Joe-BMW33]

Originally Posted by JoeFromPA

Spark plugs don’t wear out due to number of oil changes.

For those paying out of your own pocket, pay for spark plugs when usage drives it. Which is mileage.

I think the comment Joe about oil changes was just for the math. BMWs mileage timer on oil changes is 10k miles. So 6 changes is 60k miles which is when BMW wants you to change them.

I agree, oil service has nothing to do with spark plug wear.

[JoeFromPA]

Originally Posted by Joe-BMW33

I think the comment Joe about oil changes was just for the math. BMWs mileage timer on oil changes is 10k miles. So 6 changes is 60k miles which is when BMW wants you to change them.

I agree, oil service has nothing to do with spark plug wear.

Sometimes the CBS operates on time as well. So it may flag something handle based upon time and not usage.