Hi gentlemans, i had a 1999 325c, few months ago i change all the coolant system: pump, lines, radiator and coolant deposit. Everything is new, but i had this problem:

The temperature gauge mantain the same indication, so i never had an overheating, but sometimes i loose all the coolant liquid by the cover of the deposit. This happend after 2 days of use, never before. Now, sometimes i open the deposit cover in cold and release air pressure. I dont know if the coolant system had a valve for release this air or what. I also try with the screw placed on the deposit to keep only the liquid, but doesnt work.

Anybody had an idea to fix it?

Regards,

R

You should have a bleed screw on the thermostat housing, start car and let her idle, then open the bleed screw a bit (until coolant starts to flow), let coolant flow slowly (if you see bubbles in the coolant, let her flow until bubbles disappear) the tighten bleed screw and see what happens (this may take a couple of trys).

Ok, thnks a lot

if all your coolant is dissapearing and your getting air pressure in your radiator, when the car is cold, open the radiator cap and let all of the pressure out, put it back on and run the engine for 2-3 min, if you have air pressure in your radiator again it sounds like your head gasket may be blown