Author Topic: Coolant leak (Read 2265 times)

WHITEM42 · « **on:** March 18, 2009, 08:00:50 AM »

Hi All:
My M42 was parked for the winter. Coolant started to drip on to
the floor whenever the temperature drop to -25C. When the temperature
warm up, the dripping stop. The car is not running at all. All idea why
the car leaks even it is not running. The leak seems to come from
the gasket between the upper and lower timing case on the passanger
side (profile gasket?).

Thanks.

beemer1 · « **Reply #1 on:** March 18, 2009, 01:23:56 PM »

How many miles are on the car?

Check your oil, if there is a problem with the profile gasket usually you'll find a greenish milky substance on your dipstick.

Steve

doitover · « **Reply #2 on:** March 18, 2009, 02:31:03 PM »

Is it dripping from the bottom of the expansion tank? It happened to mine on one of our rare 20ish degree nights. After some googling apparently that's common when the bottom seal of the expansion tank is going bad.

Search around here, someone fixed it by siliconing it to death. The seal you need or the whole expansion tank is pretty cheap.

Jimmy Lewis · « **Reply #3 on:** March 19, 2009, 03:39:04 PM »

Yeah, it will leak until the expansion tank doesn't have enough coolant in it to provide sufficient pressure to force the coolant out of the bad seal. Luckily, BMW was smart and allowed for maintainance to the expansion tank. Look on realOEM to get an idea of how it all goes together, or do a search on here for similar issues. Basically you remove the expansion tank, smear a bunch of sealant on the end, ram it back into its little cubby hole, wait for it to dry, flush and bleed, and be on your merry way.