Burning coolant?

I agree with Roberto, actually. I was entertaining the thought today, and in concept seems okay, but why would air pockets cause overheating issues unless it was a large amount? Also, I don't think that air pockets would cause coolant to burn off, and even if so, would it escape out the exhaust or the overflow resevoir? But, I do not really know much about the cooling system or cars in general, so I could be dead wrong. Regardless, ot won't hurt to bleed out my system. Probably will flush the system and then bleed on my next day off. Should probably replace my oil as well, just so I know what's in it. And while I'm at it, I'll flush the oil system as well. Probably won't solve my mystery, but it won't hurt, either. Plus I can get a closer look at the oil and coolant for examination. Still not entirely convinced this isn't a head gasket issue.

Roberto...

I did not change the thermostat or the water pump.

Please!
DO inform me what solved my problem.

^ He has a point. Like Roberto said, it could have been simply coincidence, but that seems unlikely. Anyways, the problem's gone and that's what matters!

Originally Posted by Tyannt

Roberto...

I did not change the thermostat or the water pump.

Please!
DO inform me what solved my problem.

Coincidence is not correlation. Please read my earlier responses to you.

If it took nearly 3 weeks for all the air to evacuate itself out of my engine, without much if any being introduced into the block during my radiator change, and if in that time, there was zero overheating issues, then that is also factual evidence that you must confront.

Water levels kept falling in such a way that I actually thought I had a serious problem with my engine. I had to run various tests etc to rule out a hg or cylinder head issue.

Remember, you did bleed your radiator, and despite that your engine overheated or at least ran hot. Then your mechanic bled it and it seems to be ok. Bleeding is not rocket science. Think back to your experience. I doubt you did anything different from your mechanic.

So, i feel it was probably a coincidental fix. As I have said, it has been known to happen.

On these forums, when it comes to overheating issues, 90% of these are caused by failing water pumps and thermostats. Thus, unless you have changed these out recently, I suggest you do so. It is a regular maintenance item anyway.

Originally Posted by Tyannt

Just to add to AMK's problem, I had a 91 525 M50 doing the same thing.

Same symptoms, AND overheating, froth under the oil cap and white smoke bellowing.

Froth under the oil cap ? white smoke, billowing from the tailpipe ? And you think that this was caused by air in the engine's coolant passages ?

I suggest you call up or pay a visit to your mechanic and find out exactly what he did with your car. And if he says that all that he did was regular bleeding, then please ask him to explain how air in the water jacket causes white smoke out the tailpipe and froth under the cap.

Hot spots in your engine can certainly vapourise your coolant, but short of a HG leak or a cracked head, coolant vapour cannot reach the engine oil and cannot leak into the combustion chamber to be expelled out as white smoke.

robertobaggio20...

Quit trying so hard to be right... and contradicting yourself in the process!
Need I explain how and where?

Did you ask if I had to continually add more coolant? Did you ask to what extent I was overheating, or
if I had tried to bleed the system before my mechanic friend did? You assumed that I left the car at a shop
and may have no idea what he did.
Further, you do not understand as much as you think you do of our cooling systems. Do you know the
difference between a serial and parallel type cooling system, and which of those the M50 design is?

Do some reading on "air pockets/hot spots" in automotive cooling systems, then come back and tell me
that they cannot cause a coolant loss or overheating.

The white smoke and froth under the oil cap was simply condensation from hardly being driven,
and this occurred during the winter. Can you grasp that? Research this before you profess to know all,
unless you are simply making suggestions, clearly you've read that many overheating problems on
this car are due to faulty water pumps or thermostats, and are dwelling on that, suggesting that one
or the other MUST have been causing my problem. OBVIOUSLY neither was the cause.

Now! If you have any new thoughts on what actually solved my problem I'm open for entertainment!

Oh! FYI, my car never went to a shop, was never out of my sight, and I was present when my buddy came
to my house to bleed the system.

I repeat; no further issues!

I posted my experience as food for thought, not in disagreement with your opinions or suggestions on the
OP's situation. Why are you trying to help me with a non issue?
Is it still unclear to you what actually solved my problem?

OMG!! Could it have been that I replaced the BRASS BLEEDER PLUG with an original plastic one?

Since the mods saw fit to take out relevant posts, and since I think they are not fit to mod, let me sum things up.

Originally Posted by Tyannt

robertobaggio20...

Quit trying so hard to be right... and contradicting yourself in the process!
Need I explain how and where?

There are no contradictions in my posts.

Did you ask if I had to continually add more coolant? Did you ask to what extent I was overheating, or
if I had tried to bleed the system before my mechanic friend did? You assumed that I left the car at a shop
and may have no idea what he did.

Further, you do not understand as much as you think you do of our cooling systems. Do you know the
difference between a serial and parallel type cooling system, and which of those the M50 design is?

Obviously you tried to bleed your radiator before calling in your mechanic - you would have to be a capital fool not to, so I didn't bother to ask. ANd I know enough about our cooling systems my friend, to....

Do some reading on "air pockets/hot spots" in automotive cooling systems, then come back and tell me
that they cannot cause a coolant loss or overheating.

....tell you that hot spots in the engine will not cause you to loss coolant, as coolant vapour does not osmosize or beam itself through the metal and plastic of an engine and a radiator. They will remain trapped in the system and eventually condense back into liquid once the car cools down after shutoff.

Vapourised coolant will of course get out of the car through a ruptured hg, cracked head, or other ruptures in the rad and rad hose circuit.

The white smoke and froth under the oil cap was simply condensation from hardly being driven,
and this occurred during the winter. Can you grasp that? Research this before you profess to know all,
unless you are simply making suggestions, clearly you've read that many overheating problems on
this car are due to faulty water pumps or thermostats, and are dwelling on that, suggesting that one
or the other MUST have been causing my problem. OBVIOUSLY neither was the cause.

As mentioned, it was misleading to include mere condensation in your original writeup and suggest that this had something to do with coolant loss.

Now! If you have any new thoughts on what actually solved my problem I'm open for entertainment!

Oh! FYI, my car never went to a shop, was never out of my sight, and I was present when my buddy came
to my house to bleed the system.

I repeat; no further issues!

I posted my experience as food for thought, not in disagreement with your opinions or suggestions on the
OP's situation. Why are you trying to help me with a non issue?

And I responded in good faith likewise. As mentioned, 1.5 expansion tanks worth of air made it through my engine slowly over the course of 3 weeks without causing any overheating in the least. If you know how much 1.5 expansion tanks of air are worth...that's something like 3 litres or so. Our cooling system's capacity is 11 litres. Conclusion ? Reports of overheats due to air pockets are greatly greatly exaggerated. I suspect your problem got solved coincidentally, which means its still lurking, and most E34 overheats are caused by buggy thermostats and wps so that's where I'd attack first, just in case. I could be wrong of course but I highly doubt that. And my mechanics who do BMWs all day long confirm that trapped air pockets is not a known problem for our E34 engines, both of them, unlike what your mechanic seems to think.

Its your car and you are welcome to carry the risk. Pm me if you feel you need further clarification.

rgds, Roberto

Since the mods saw fit to take out relevant posts, and since I think they are not fit to mod, let me sum things up.

Originally Posted by Tyannt

robertobaggio20...

Quit trying so hard to be right... and contradicting yourself in the process!
Need I explain how and where?

There are no contradictions in my posts.

Did you ask if I had to continually add more coolant? Did you ask to what extent I was overheating, or
if I had tried to bleed the system before my mechanic friend did? You assumed that I left the car at a shop
and may have no idea what he did.

Further, you do not understand as much as you think you do of our cooling systems. Do you know the
difference between a serial and parallel type cooling system, and which of those the M50 design is?

Only a capital fool would not bleed the radiator before calling in a mechanic and you clearly are not a capital fool so i didn't bother with that question. And I know enough about our cooling systems my friend, to....

Do some reading on "air pockets/hot spots" in automotive cooling systems, then come back and tell me
that they cannot cause a coolant loss or overheating.

....tell you that hot spots in the engine will not cause you to loss coolant, as coolant vapour does not osmosize or beam itself through the metal and plastic of an engine and a radiator. It will remain trapped in the system and eventually condense back into coolant once the car cools down after shutoff.

Vapourised coolant will of course get out of the car through a ruptured hg, cracked head, or other ruptures in the rad and rad hose circuit.

The white smoke and froth under the oil cap was simply condensation from hardly being driven,
and this occurred during the winter. Can you grasp that? Research this before you profess to know all,
unless you are simply making suggestions, clearly you've read that many overheating problems on
this car are due to faulty water pumps or thermostats, and are dwelling on that, suggesting that one
or the other MUST have been causing my problem. OBVIOUSLY neither was the cause.

As mentioned, it was misleading to include mere condensation in your original writeup and suggest that this had something to do with coolant loss.

Now! If you have any new thoughts on what actually solved my problem I'm open for entertainment!

Oh! FYI, my car never went to a shop, was never out of my sight, and I was present when my buddy came
to my house to bleed the system.

I repeat; no further issues!

I posted my experience as food for thought, not in disagreement with your opinions or suggestions on the
OP's situation. Why are you trying to help me with a non issue?

And I responded in good faith. As mentioned, 1.5 expansion tanks worth of air made it through my engine slowly over the course of 3 weeks without causing any overheating in the least. If you know how much 1.5 expansion tanks of air are worth...that's something like 3 litres or so. Our cooling system's capacity is 11 litres. Conclusion ? Reports of overheats due to air pockets are greatly greatly exaggerated and likely to be false positives, concealing other issues. I suspect your problem got solved coincidentally (not unheard of in old components), which means its still lurking, and most E34 overheats are caused by buggy thermostats and wps so that's where I'd attack first, just in case. I could be wrong of course but I highly doubt that. And my mechanics who do BMWs all day long confirm that trapped air pockets is not a known problem for our E34 engines, both of them, unlike what your mechanic seems to think.

Its your car and you are welcome to carry the risk. Pm me if you feel you need further clarification.

rgds, Roberto

Originally Posted by robertobaggio20

Since the mods saw fit to take out relevant posts, and since I think they are not fit to mod, let me sum things up.

robertobaggio20...

What you state as "osmosiZe" is properly "osmosis"

I said hot spots/ air pockets can cause coolant loss or overheating, simply.

I did NOT say that they cause coolant to evaporate into thin air!

Again, I was not asking for your advice here!

Originally Posted by Tyannt

robertobaggio20...

What you state as "osmosiZe" is properly "osmosis"

You must be a lady or someone who is not a native english speaker, or perhaps you have a cold as well.

I know what I said. Reread it. Perhaps it will help to get reacquainted with the rules of grammar for the english language. The inimical Dr Thornton to the rescue :



That would at least help to put you into a better mood.

Originally Posted by Tyannt

robertobaggio20...

I said hot spots/ air pockets can cause coolant loss or overheating, simply.

I did NOT say that they cause coolant to evaporate into thin air!

Again, I was not asking for your advice here!

But i am asking for yours ! Please help me understand how (a) hot spots and (b) air pockets, could cause coolant loss in a sealed cooling system. Thank you.



rgds,
Roberto

BTW his name is not Tyrant...

Originally Posted by paperplane94

BTW his name is not Tyrant...

I think we're dealing with a lady...

Steve Sir, I need corroboration on something. I recall you did a coolant system overhaul that included changing the radiator, around 2-3 years back. You posted up a very detailed diy on it with loads of pictures, as I recall.

You obviously bled the radiator after fixing everything up. Did you monitor coolant levels daily after that? How did it behave? Did it fall, and did you top up, and if so, at which point (i.e days or weeks) did it stop falling? Could you estimate the number of expansion tanks-worth of topups you had to do ?

As mentioned, when I changed my rad and bled the radiator both hot and cold, I still had to top up for nearly 3 weeks thereafter before coolant levels stopped moving from full, and I'm estimating that it involved 1.5 exptanks worth of extra coolant.

Thank you.


rgds,
Roberto

Roberto!
If you believe that I'm a Lady, you've lost all faith from me that you ever had a reputation of
being a nice guy! Also, you should know that women really don't like whiny babies who insist
on having to be right all the time! But, what do I know... I'm male!

It appears you're seeking affirmation; is this to convince me that if I didn't need to top up
my coolant to the tune of 1.5 expansion tanks, it MUST have been my pump or thermostat!
Continue if you must, it's entertaining!

Coolant loss? Booby you haven't done your homework!! Search is your friend!

FYI... Your good Dr. Thornton failed to convince me that "osmosize" was a legitimate word!

The Tyrant!

Originally Posted by Tyannt

Roberto!
If you believe that I'm a Lady, you've lost all faith from me that you ever had a reputation of
being a nice guy!

The Tyrant!

There you go. You actually believed that I had such a reputation to begin with just because I said so. You are surely a chick.

And considering your distinct brand of sarcasm in your earlier posts.....a pretty pouty, or a pouty pretty one, I bet.

And considering that you're not the least bit vulgar, you might actually be a nice gal !

In fact......I think I know almost exactly what you might look like.




Here's hoping that unlike the car in the ad above, your "engine" might be an m"50" instead of an m"20".

;->>>


cheers,
R

p.s. Fine, if you don't want to explain how vapourised coolant can escape from sealed systems, which proposition flies in the face of logic thus placing the burden of proof on the antagonist, then I shall take it that you've conceded the point.....and are pouting as you read this.
p.p.s. I am one of the guys in that commercial ! lolololol
.

Originally Posted by robertobaggio20

Steve Sir, I need corroboration on something. I recall you did a coolant system overhaul that included changing the radiator, around 2-3 years back. You posted up a very detailed diy on it with loads of pictures, as I recall.

You obviously bled the radiator after fixing everything up. Did you monitor coolant levels daily after that? How did it behave? Did it fall, and did you top up, and if so, at which point (i.e days or weeks) did it stop falling? Could you estimate the number of expansion tanks-worth of topups you had to do ?

As mentioned, when I changed my rad and bled the radiator both hot and cold, I still had to top up for nearly 3 weeks thereafter before coolant levels stopped moving from full, and I'm estimating that it involved 1.5 exptanks worth of extra coolant.

Thank you.


rgds,
Roberto

After the one post-rebuild bleed required, I had to top off the expansion tank only once the following day. It required approximatley 3-4 lines on the tank to bring it to the cold level during my check (engine cold of course). No coolant level drop thereafter.

I had to do the same thing after I recently had my heater core replaced by my indy mech.

Roberto!

You might request that the mods make a sticky entitled

"Note to female forum members re: "English grammer"

Roberto, and to all:

Lil ol me did in fact, originally type "HOT SPOTS can develop; areas where air gets trapped and
can "BURN OFF COOLANT", cause coolant loss and overheating."

I agree that Hot Spots do not actually vaporise coolant!

Originally Posted by Tyannt

Roberto, and to all:

Lil ol me did in fact, originally type "HOT SPOTS can develop; areas where air gets trapped and
can "BURN OFF COOLANT", cause coolant loss and overheating."

I agree that Hot Spots do not actually vaporise coolant!

Actually my dear, hot spots can and probably do vapourise coolant. However, that vapourised coolant, unless it escapes the system through a hg leak, a cracked head, or a rupture or loose fitting somewhere in the radiator and cooling hoses circuit, will inevitably cool and condense back into solution once the car is shut down.

The vapourised coolant can form an gaseous barrier between hot metal and liquid coolant, thus preventing the hot metal from being cooled, and thus resulting in overheating.

That's in theory. However, in practice, I very much doubt that this is significant enough to actually cause problems. Coolant is being circulated and it does push air and vapourised coolant throughout the system and away from the insulated hot spot.

Originally Posted by Tyannt

Roberto!

You might request that the mods make a sticky entitled

"Note to female forum members re: "English grammer"

Couldn't resist !

Roberto!

You're gay, right? NOT interested!!