Why does my e36 hate coolant so much?

Soldato
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Following the saga prior to the trackday, the coolant has continued to fall, so I guess the stat housing was a waste of time and money. I can't identify where it is going to, but until I can get some UV dye in it, why won't it take any damn coolant!?
Today I get in the car after work and get a warning, the expansion tank is way way down, so I end up topping it up using cups from the water cooler, not a good look I have to say. Drove it home via petrol station and motorway gridlock, no heat the whole time below 3000rpm, freezing in this weather! Gauge always in the middle.

Trying to top it up and bleed it out is seemingly impossible though, I fill up the tank but every time I fill it to near the top, I get huge air bubbles coming up, and it burps ALL of the water out, at which point both rad hoses are empty and only steam comes out of the bleeder. Fill it up again, same thing happens. Flooded the garage doing this.

In the end I did the best I could with the engine off and just squeezing the pipes, but still, I have heaters only with the rpm up.

I just don't understand why it burps it all out every time though. Is it possible that there is something wrong with the expansion tank thing? I noticed that a noise comes from in there when you squeeze the hoses.

I'm going to put the old stat and housing back on, ever since I fitted this new one I've had massive problems which didn't exist before. I wonder about the radiator though, maybe this is the root cause of all the problems?
 
Soldato
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Coke (other soft drinks are available) bottle time. 2L bottle, cut the fat end off, put it in the filler spout and fill it with water. It puts the water head way above the pipework & bleed points, gets all the air out.

Very useful on some french stuff where the water bottle is lower than the bleed points.
 
Associate
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Have you switched out the waterpump for one with a metal impellor? What sealant did you use when you switched out the stat housing? You have to be so so careful when you change the stat housing as they are very delicate and crack as you tighten them.

To bleed mine I got it up to temp (actually slightly above, the needle rises very quickly once its past half way) and got it on a steep hill with the bonnet facing up. Then I kept the engine running and used a very long screw driver to release the bleed valve until it settled then topped up again until the steam stopped and the water started. That was two years ago and its been fine ever since.
 
Soldato
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does your expansion tank have a small return line (usually from the top of the radiator)

if that is blocked it can lead to big airlocks, overheating and the engine burping/volcanoing all its coolant out
 
Soldato
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No sealer on the housing just rubber gaskets. It's metal anyway so won't be breaking easily.
Expansion tank is built into the radnd is more complex than simply a bottle.
Coke bottle trick sounds handy I will try that thanks.
 

DRZ

DRZ

Soldato
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Getting the car up at the front will help. They are an absolute nightmare to bleed and there is a procedure to follow with the bleed screws and various lengths of time running at certain engine speeds.
 
Soldato
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You have got the time of year on your side.
Top it up, go for a hardish drive, stop and look for steam in the cold night air, I am sure you will find something.
 
Associate
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No sealer on the housing just rubber gaskets. It's metal anyway so won't be breaking easily.
Expansion tank is built into the radnd is more complex than simply a bottle.
Coke bottle trick sounds handy I will try that thanks.

Its been a while since I did it, but are the gaskets the little rubber circles that sit inside the housing? I couldnt get them to seal 100% so I used sealant and that solved the problem. Never saw a metal housing, good idea though as the black plastic ones loved to crack.
 
Soldato
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I think it's the heater matrix causing a problem, I'm now getting a misting on the windows even with the AC on. I thought maybe the AC had become defective so I tried knocking it off, within 30 seconds the windows got majorly fogged up. I can't really smell any coolant though, maybe just a tiny hint of the smell. I also don't have any dampness in the carpet, maybe any leaking spills out of the evaporator drain, there is always a small puddle under the transmission area.
Not looking forward to investigating this one, stripping shoes e36 revealed this is a nightmare job even with the whole dash out of the car :/
 
Man of Honour
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They are an absolute nightmare to bleed and there is a procedure to follow with the bleed screws and various lengths of time running at certain engine speeds.

Clarkey says you are wrong!

Clarkey said:
Bleeding a BMW is made out to be a nightmare by loads of people but it's no different to any other car.
:p
 
Soldato
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Well I guess I'll eat my words now. I have done this without any kind of issue 4 or 5 times before though on identical cars, which leads me to believe there is something faulty on my car.
 
Soldato
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It finally broke down, had to abandon at 1am, it turned itself into a kettle. Could be curtains for the e36, a golden opportunity to go back to jap scrap maybe...
 
Soldato
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double you tee eff

what did it do to itself?

apparently it had no coolant in it, I went back to it this morning and it took 5 litres. Now it's back to it's normal business of running fine but having no heat below 1500. Bear in mind though, before I went out last night, the coolant warning came on and I put some in so it somehow lost an awful lot.
 
Soldato
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and no sign of an obvious leak?

get a compression tester if you think its dead-dead

then, get a new 2.8

put the current one on an engine stand, rebuild it, but with a massive turbo on the side
 
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