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E34 (1989 - 1995)

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Old 10-12-2012, 09:22 PM
robertobaggio20 robertobaggio20 is offline
Location: earth
Join Date: Oct 2009
Posts: 3,403
Mein Auto: car
You mention alot about bubbles but you are unclear. Where were the bubbles coming from.

Did you continuously feed the expansion tank with a slow running hose ? Why ?

Fill up the expansion tank and remove the rad cap and bleed screw. Start the engine and let it idle. Since it does not overheat when its not being driven, you can come back 15-30 minutes later.

Bubbles coming out through the bleed screw is ok, and even then, they wouldn't come out for like 30 minutes unless you've completely drained your block and radiator and are filling everything up from scratch.

If you are getting bubbles IN THE EXPANSION TANK, then you've got a serious problem.

The auxiliary water pump only controls hot water running through the dashboard i.e. cabin heater. It plays no functional role in the cooling system. Please ignore it for now, but do ask your friend to reconnect it back on Monday, its just a 2 minute job for someone who knows his way around this car.

There's a good possibility that its your water pump or thermostat that is busted. But, if you are getting bubbles IN THE EXPANSION TANK, you've got a very serious problem.

You should go back and ask your son what he did to the car (or what others might have done to the car) in the days leading up to this situation.

Good luck.

Last edited by robertobaggio20; 10-12-2012 at 09:24 PM.
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