93 325i overheating! - BMW Forum

Insane93E36 · 10-24-2006, 09:34 PM

Just got my 93 325i and i had a huge problem a week after i got it. First the Coolant recovery tank exploded on it and i replaced it with a new unit from BMW. Then the car started overheating like crazy, never let it hit the red and stopped for it to cool down. So i dug further and ended up replacing the thermostat, the old one came out in 5 peices it was trashed. Still the problem persisted this time it blew a hose back on the fire wall at the heater control valve. Replaced the heater control valve with yet another new one from BMW. So far a replaced recovery tank, thermostat and heater control valve. I have bled the system for air properly and still the car will over heat, i am lost on this one, any ideas? The head gasket is fine and there are no visible leaks anywhere on the motor!

WarNox · 10-24-2006, 10:58 PM

hey, its probably the water pump.

Insane93E36 · 10-25-2006, 09:28 AM

new water pump also, was put on 2 days before purchase, this is all just drivin me nutz, but thanx i'll look back into it!

rborak318iS · 10-25-2006, 11:34 AM

Check out the radiator, though you said it isnt leaking it may be worth looking into. They can go bad or get cracked.

jnstrcklnd · 10-25-2006, 02:50 PM

Quote:

Originally Posted by Insane93E36

Just got my 93 325i and i had a huge problem a week after i got it. First the Coolant recovery tank exploded on it and i replaced it with a new unit from BMW. Then the car started overheating like crazy, never let it hit the red and stopped for it to cool down. So i dug further and ended up replacing the thermostat, the old one came out in 5 peices it was trashed. Still the problem persisted this time it blew a hose back on the fire wall at the heater control valve. Replaced the heater control valve with yet another new one from BMW. So far a replaced recovery tank, thermostat and heater control valve. I have bled the system for air properly and still the car will over heat, i am lost on this one, any ideas? The head gasket is fine and there are no visible leaks anywhere on the motor!

You said the thermostat was in 5 peoces. Are you sure you got them all out? Could be plugging something up and causing back pressure.

WarNox · 10-25-2006, 04:32 PM

hmm ok then.

when you just leave the car running does your fan come on after a while? the one that comes out of your waterpump? it always spins but when it gets hot it should spin much faster.

Insane93E36 · 10-27-2006, 08:56 PM

welli think we figured it out, after many exhausting hours of trouble shooting and testing, the problem was an air pocket in the system that we were unable to get during conventional bleeding of the cooling system, so we solved the problem by vacuming the system and it seems to be running fine now, no more overheating, no more pressure, just smooth running as it should be. Thanx for all of the suggestions and it was helpful.

Tony

peluso1228 · 01-28-2012, 12:51 AM

hi tony, my name is juan \ i have the exact problem , expantion tank explote , i did replace my termosthat was bad ,thats why blow my tank out, new coolant , bleeding also , still overheating....how you vacuum the system ?, please let me know

DickDonlevy · 05-01-2012, 02:34 PM

Bleeding the air on an E36 is notoriously difficult.
The last time I did it it took about 4 hours, jacking up different corners of the car in turn to move the air pockets along. Wish I'd have read your post earlier!

Lord Vader · 05-02-2012, 12:33 AM

Dick this thread was 6 years old.