Cooling System

BTW I find that this has been a great read and applaud all of the work so far.

Originally Posted by sirstopher

BTW I find that this has been a great read and applaud all of the work so far.

+1 I can't wait to see a resolution.

Originally Posted by SFbay

Super update:
I removed TB and look what I found:
- previous owner was a btch
- this Y pipe is actually has a bleeding valve inside, so if there is any smallest tiny leak, the system will never get bleeded!!!!
So I guess it was a number one problem, but I need oem clamps to install oem one. FK
This is very very important hose, replace it anyways even if no leaks bc you don't know if that valve is working!!!

Ouch, I just bought the pipe from dealer, my cost $58.. and that is def. not stock! Me and Paper were talking about that needle valve a few days ago, and that hose is called a vent hose, so that's why I bought a new one.. it's got a little plastic T on the end.. I am really hoping that it is a big cause for not bleeding. Also, the factory hose does use hose clamps to install to heads.. but not to a copper T

Originally Posted by cmpcpro

Ouch, I just bought the pipe from dealer, my cost $58.. and that is def. not stock! Me and Paper were talking about that needle valve a few days ago, and that hose is called a vent hose, so that's why I bought a new one.. it's got a little plastic T on the end.. I am really hoping that it is a big cause for not bleeding. Also, the factory hose does use hose clamps to install to heads.. but not to a copper T

Yes but at leas the brass one will not fall apart like my OEM did.

Originally Posted by First_745Li

+1 I can't wait to see a resolution.

Originally Posted by B7M4W5

Yes but at leas the brass one will not fall apart like my OEM did.

Well evidently it did, he said it was leaking I thought..

Originally Posted by SFbay

Super update:
I removed TB and look what I found:
- previous owner was a btch
- this Y pipe is actually has a bleeding valve inside, so if there is any smallest tiny leak, the system will never get bleeded!!!!
So I guess it was a number one problem, but I need oem clamps to install oem one. FK
This is very very important hose, replace it anyways even if no leaks bc you don't know if that valve is working!!!

wtf @ the first pic. man ppl these days the hose was prolly bad and instead of replacing the whole thing he replaced the T with some random auto parts or hardware store brass/copper T and thought itd be a great solution
and about OEM clamps are you talking about the hose clamps with the wierd t shaped loop at the end? I hate those things.
so far its been the same thing I run relatively cool 92ish on the regular. only gets higher up directly after highway runs but shortly thereafter drops back down. I will continue to regularly monitor my coolant temperatures from time to time in case it starts to climb.
How is more of the testing going still everything going okay (besides this leak)

Originally Posted by 745iguy

wtf @ the first pic. man ppl these days the hose was prolly bad and instead of replacing the whole thing he replaced the T with some random auto parts or hardware store brass/copper T and thought itd be a great solution
and about OEM clamps are you talking about the hose clamps with the wierd t shaped loop at the end? I hate those things.
so far its been the same thing I run relatively cool 92ish on the regular. only gets higher up directly after highway runs but shortly thereafter drops back down. I will continue to regularly monitor my coolant temperatures from time to time in case it starts to climb.
How is more of the testing going still everything going okay (besides this leak)

So aux fan kicks in from 105 to 103 now??

Originally Posted by SFbay

So aux fan kicks in from 105 to 103 now??

no im still running the same as the ss i had posted 92 highest is like 101-102 and only directly after stopping from a decent 60mph+ ride on the highway. never reaches 105 from me watching in INPA. but i will continue to monitor this from time to time. i dont want to run at 105C

37 high 25 low today in Fahrenheit

Originally Posted by 745iguy

no im still running the same as the ss i had posted 92 highest is like 101-102 and only directly after stopping from a decent 60mph+ ride on the highway. never reaches 105 from me watching in INPA. but i will continue to monitor this from time to time. i dont want to run at 105C

Bc you're in MA that's why 92ish
I didn't get the clamps so my car is kinda stuck for today

Originally Posted by SFbay

Bc you're in MA that's why 92ish
I didn't get the clamps so my car is kinda stuck for today

Well it's getting down to 45f here at night, and still running the same temp.. yet Paper runs like his at 92-ish.. must be DME opening early or something.. Well I have everything together so I will replace cooling system including water pump tomorrow morning.

The clamps for that new hose are just regular hose clamps with bolts.. they say BMW on them.. Mine are fine but I bought 4 extra ones they were only a dollar at the dealer.

Originally Posted by cmpcpro

Well it's getting down to 45f here at night, and still running the same temp.. yet Paper runs like his at 92-ish.. must be DME opening early or something.. Well I have everything together so I will replace cooling system including water pump tomorrow morning.

The clamps for that new hose are just regular hose clamps with bolts.. they say BMW on them.. Mine are fine but I bought 4 extra ones they were only a dollar at the dealer.

Original bmw clamps are 100% better than Chinese piece of crp I have. I still cannot believe it can run 92c unless its enough cooling without radiator big circuit.
I saw one car and it was running at 85c but for some reason boiler was always on and tstat was open all the time after it warmed up, idk what caused DME to open it, but as a result his aux fan was always on and finally died.

well is it possible that because my DME isnt US spec that maybe it opens tstat differently? just trying to think if not then i guess its just normal?
my aux fan runs only when idling but cuts out fairly quickly, i never idle around for too long really to see how often but ive seen it in action a few times. (not as of lately as i can recall i will look for that next time)
lower radiator hose is at a pretty constant 60something while on most of the time, as long as i dont do a spirited run it wants to stay around 92ish, though (other temp not lower hose)

If it would help, I could read mine with INPA tomorrow as I just had the coolant pipe now AGA, thermostat, expansion tank and water pump replaced with full flush.

I would be interested in what it's reading.

Where in INPA do I read the temp?

I guess the only other way for me to know is wait til warmer weather also.

Originally Posted by sirstopher

If it would help, I could read mine with INPA tomorrow as I just had the coolant pipe now AGA, thermostat, expansion tank and water pump replaced with full flush.

I would be interested in what it's reading.

Where in INPA do I read the temp?

when you go to the engine ME9 for n62 go to status and read i think it is analog 1, it will bring up the screen from my photo.

also im very interested in seeing this also from as many other 7s as possible tbh, itd be nice to have as many examples as possible

Originally Posted by 745iguy

when you go to the engine ME9 for n62 go to status and read i think it is analog 1, it will bring up the screen from my photo.

also im very interested in seeing this also from as many other 7s as possible tbh, itd be nice to have as many examples as possible

I will post report tomorrow and note exterior temp. I will run the car up to operation temp.

Originally Posted by sirstopher

I will post report tomorrow and note exterior temp. I will run the car up to operation temp.

i look forward to seeing what it looks like after so many critical components of the cooling system replaced.
if its that hot (100+) even with that IDK how my car would be 92 because its cold, maybe im under the false presumption that the car will try to get to operating temp and keep the tstat closed until it does ? papers is around the same as mine and hes in a slightly warmer climate than i am

Originally Posted by sirstopher

I will post report tomorrow and note exterior temp. I will run the car up to operation temp.

Thanks! I am very interested in seeing that myself.. Paper's car is a fine specimen of E65ness as he is original owner and 60k miles.. probably babied.. I am wondering if these cars ran cool in the early years and started to go up after leaks, etc.. but with a 105c tstat, that just doesn't make sense.. so will be nice to see what yours looks like after all the overhauls.

This thread is very interesting....even though it's technically way above my head. I'm not experiencing this "overheat" or leaking symptom in my E66, nor in F02, but my inclination is what you're finding here could be potentially big and worth to elevate a BMW recall. Can one of you guys write up a separate summary post that indicates clear root cause and preventative actions for the rest of us? We can even gather the whole gang and submit complaints to BMW-NA and other consumers protection agency.

Sample elements of the complaint:

1. The events leading up to the "failure" that you are describing.
2. How often the failure occurs and its consequences.
3. What has been done to correct the failure, such as repairs or replacements.

Much appreciated!

Originally Posted by hd750Li

This thread is very interesting....even though it's technically way above my head. I'm not experiencing this "overheat" or leaking symptom in my E66, nor in F02, but my inclination is what you're finding here could be potentially big and worth to elevate a BMW recall. Can one of you guys write up a separate summary post that indicates clear root cause and preventative actions for the rest of us? We can even gather the whole gang and submit complaints to BMW-NA and other consumers protection agency.

Sample elements of the complaint:

1. The events leading up to the "failure" that you are describing.
2. How often the failure occurs and its consequences.
3. What has been done to correct the failure, such as repairs or replacements.

Much appreciated!

Sure I can write about it with some technical terms, my internal combustion engines mechanical engineer degree might help here
But... They know it pretty well and they did it on purpose. Their explanation would be:
We run our engines at 105C just bc of higher emission standards which is total BS. They will also say that their tstats are so advanced so they can open it whenever they want, but they don't tell you that that boiler doesn't work that fast and very often dies (you won't even get any CEL if boiler died).
Myth 1:
Bc of emission standards.
Sure higher combustion temp will help to burn it faster, but there are some limits there!! Did you notice that in summer time your car is kinda slowish??? Well it's all bc of detonation going on inside the cam!!!
Bmw has knock sensors which adjusts timing on the fly so you cannot hear any detonation. And yes you can easily put 87 in your engine and you won't hear any knocks, only reduced power. Sooo high temp in your engine will prematurely kill your pistons and rings and head gaskets.
Yes it's amazingly can sustain that heat for a while and later we get blue smoke lol)
Myth 2. Higher temp will get you more power:
And here is some nonsense from bmw: every S V8 engine for m cars still runs at 79C max!! for example S54 runs at 78, s62 at 79 and this is the same V8 and V10 technology as M62(runs at 105).... So wtf??? And all these m cars have same catalytic converters!! And it's all fine with "high emission" standards!!! And M cars actually last pretty well even with the way they are being used on the track!
S54 can easily make 200km without any serious problems related to cooling!!! And more importantly all these sporty tstats don't have any fancy boilers inside, but why? what about higher temp will get your better combustion theory??? And M cars have way more power than standard 105C engines. Ever thought why bmw engines from 90 still running okay without smoking even at 300-400k miles and don't forget that inline 6 with 4 valves per cylinder still makes 25-28 mpg hwy??? Ok it was from bmw stand point. Other car makers still have 90-95 tstats (Mercedes, Toyota, honda, ) but wv took the same idea from bmw and they have 100-105C tstats starting from 1998 and look their engines cannot even make to 60km!! Literally Oil gets cooked on those oil passages!!! So many failures!!!! Read about 4 cyl turbo engines recalls. Though at least V8 run at 92 so premium cars are ok.
So why all other cars are ok with normal tstats and they all comply with emission standards pretty well????
At least bmw didn't do the same thing for inline 6 engines so the best selling 5 series are at lower risk bc it's 95C, otherwise nobody would buy it!!! Wtf 8yr old e60 costs more than e65?? E60 with V8 has horrible reputation everywhere!!! Ppl are scared to death of those N62 and M62 time bombs. Oops and one more thing: that 105C from 2001 is still the same even for 2012 engines!!! I can only imagine how long those turbocharged engines with 105 can sustain, it's like suicidal for the engine.
yes it was very little from internal combustion theory.
Here is some thermodynamics:
As you all know water inside the hose is pressured about 200psi which is HIGH! They did it that way so the water won't be boiling at 105-110C but as you all know any high pressure will put the system on the edge: all hoses, all gaskets are at high risk of failure!! That's why we all sooner or later will get coolant pipe leak and other leaks!!! And tiny leaks are not easy to find on the car bc when you drive it there is lots of vibration and therefore you might get some air in the system easily, that's why they built self bleeding system which removes air every time it gets there. It only works if system is perfect.
And therefore bmw recommends 2-3 yrs cooling system overhaul (pricey). Ever thought why Toyota needs it once in 10yrs??
And high temp will kill all rubber gaskets very quick.... Every single fking gasket leaks in 105C engine even with 50km plus any oil leak from the engine will kill your suspension rubber bushings easy. If you look at inline 6 with 200km it would look pretty good.
Oh almost forgot: high temp will kill your tranny as well bc tranny cooling is linked to the main radiator!
My conclusion is that if we had 90C tstats in our V8 would outlast any similar engine bc they are built to sustain that crazy heat for a while already! Mpg would be still the same if not better, think about it how much power that huge aux fan uses every time???

In other words if you buy new bmw with V8 or V12, retrofit tstat to 85-90C , put only 0w40 synthetic oil, do 5000mls oil change, you can easily make 200km without any serious problems!! Btw my 95C tstat will fit any brand new bmw. And Toyota and lexus would suck bc they are far away from technology and handling stand point.
But the problem here is bmw won't make any money from rich ppl.... You think rolls Royce ppl would complain about it??? They will just get a new engine and tranny swapped every 100k miles btw at least rolls Royce has bigger radiator and tranny cooler, but still the same 105C design.
Having 105C tstat is like playing with the fire: you never know if your coolant is boiling

Originally Posted by SFbay

Sure I can write about it with some technical terms, my internal combustion engines mechanical engineer degree might help here
But... They know it pretty well and they did it on purpose. Their explanation would be:
We run our engines at 105C just bc of higher emission standards which is total BS. They will also say that their tstats are so advanced so they can open it whenever they want, but they don't tell you that that boiler doesn't work that fast and very often dies (you won't even get any CEL if boiler died).
Myth 1:
Bc of emission standards.
Sure higher combustion temp will help to burn it faster, but there are some limits there!! Did you notice that in summer time your car is kinda slowish??? Well it's all bc of detonation going on inside the cam!!!
Bmw has knock sensors which adjusts timing on the fly so you cannot hear any detonation. And yes you can easily put 87 in your engine and you won't hear any knocks, only reduced power. Sooo high temp in your engine will prematurely kill your pistons and rings and head gaskets.
Yes it's amazingly can sustain that heat for a while and later we get blue smoke lol)
Myth 2. Higher temp will get you more power:
And here is some nonsense from bmw: every S V8 engine for m cars still runs at 79C max!! for example S54 runs at 78, s62 at 79 and this is the same V8 and V10 technology as M62(runs at 105).... So wtf??? And all these m cars have same catalytic converters!! And it's all fine with "high emission" standards!!! And M cars actually last pretty well even with the way they are being used on the track!
S54 can easily make 200km without any serious problems related to cooling!!! And more importantly all these sporty tstats don't have any fancy boilers inside, but why? what about higher temp will get your better combustion theory??? And M cars have way more power than standard 105C engines. Ever thought why bmw engines from 90 still running okay without smoking even at 300-400k miles and don't forget that inline 6 with 4 valves per cylinder still makes 25-28 mpg hwy??? Ok it was from bmw stand point. Other car makers still have 90-95 tstats (Mercedes, Toyota, honda, ) but wv took the same idea from bmw and they have 100-105C tstats starting from 1998 and look their engines cannot even make to 60km!! Literally Oil gets cooked on those oil passages!!! So many failures!!!! Read about 4 cyl turbo engines recalls. Though at least V8 run at 92 so premium cars are ok.
So why all other cars are ok with normal tstats and they all comply with emission standards pretty well????
At least bmw didn't do the same thing for inline 6 engines so the best selling 5 series are at lower risk bc it's 95C, otherwise nobody would buy it!!! Wtf 8yr old e60 costs more than e65?? E60 with V8 has horrible reputation everywhere!!! Ppl are scared to death of those N62 and M62 time bombs. Oops and one more thing: that 105C from 2001 is still the same even for 2012 engines!!! I can only imagine how long those turbocharged engines with 105 can sustain, it's like suicidal for the engine.
yes it was very little from internal combustion theory.
Here is some thermodynamics:
As you all know water inside the hose is pressured about 200psi which is HIGH! They did it that way so the water won't be boiling at 105-110C but as you all know any high pressure will put the system on the edge: all hoses, all gaskets are at high risk of failure!! That's why we all sooner or later will get coolant pipe leak and other leaks!!! And tiny leaks are not easy to find on the car bc when you drive it there is lots of vibration and therefore you might get some air in the system easily, that's why they built self bleeding system which removes air every time it gets there. It only works if system is perfect.
And therefore bmw recommends 2-3 yrs cooling system overhaul (pricey). Ever thought why Toyota needs it once in 10yrs??
And high temp will kill all rubber gaskets very quick.... Every single fking gasket leaks in 105C engine even with 50km plus any oil leak from the engine will kill your suspension rubber bushings easy. If you look at inline 6 with 200km it would look pretty good.
Oh almost forgot: high temp will kill your tranny as well bc tranny cooling is linked to the main radiator!
My conclusion is that if we had 90C tstats in our V8 would outlast any similar engine bc they are built to sustain that crazy heat for a while already! Mpg would be still the same if not better, think about it how much power that huge aux fan uses every time???

In other words if you buy new bmw with V8 or V12, retrofit tstat to 85-90C , put only 0w40 synthetic oil, do 5000mls oil change, you can easily make 200km without any serious problems!! Btw my 95C tstat will fit any brand new bmw. And Toyota and lexus would suck bc they are far away from technology and handling stand point.
But the problem here is bmw won't make any money from rich ppl.... You think rolls Royce ppl would complain about it??? They will just get a new engine and tranny swapped every 100k miles btw at least rolls Royce has bigger radiator and tranny cooler, but still the same 105C design.
Having 105C tstat is like playing with the fire: you never know if your coolant is boiling

It angers me everytime I think about it.. Everyone at my dealer knows exactly how I feel, I've spread it everywhere there.. I woke up to do my cooling system, and low and behold it's raining.. of course.. just waiting out the rain now.

I work for Toyota in Gtown and I've been involved in a couple of recall problems in the past.Usually has to be a safety related.Very directly,we have actually had rear ends fall out of the first sienna van with bad welds!No recall .Reliability I'm afraid will not get you a recall.It should but...On another note mine goes to 107c at 500rpm.At 750rpm never goes above 105c,never.In the summer It idles at 750rpm with A/C on.In winter 500rpm always with any setting on climate control.

OK, please allow me to summarize the problem based on your perspectives, experiences and knowledges:

Root cause: N62 and M62 engines equip with 105C-thermostat which was introduced by BMW in 2001. These are simple facts that we all know, BMW cooling fluild is a 50-50 mix of distilled water and BMW antifreeze, and 105 C is above water-boiling point. High-operating temperature can deteriorate rubber gaskets and eventually cause engine or coolant leaks. In addition, coolant being pressurized at high-pressure (by the water pump?) can also put cooling hoses at greater risk of failure.

Preventative Actions: Retrofit 95C-thermostat and replace OEM-plastic-propeller water pump by a metal propeller one. More frequent oil change. Any others?

Please feel free to correct me. Any information for the appropriate replacement parts and associated cost?