New Tstat, Leaking Coolant, No Heat, Overheating Problem!! Please HELP!
 

Hi All,

I am new to the bmw and 318ti scene and got the car about 3 weeks ago. It is a 97 318ti with the m44 motor in it. Well, when I got the car, it would take about 30 minutes to get to 12 o'clock on the temp gauge, blowing warm air at best - this told me that the thermostat is stuck. So, I ordered a BEHR one from ebay and put it on last night. It was dark, wet and cold (NYC) and was hard to really see anything since I park it on the street. I removed the thermostat and broke one of the lower bolts (do not know how that happened and really didn't worry about it at the time) The new thermostat came with the gasket, so I did not put on any of the RTV stuff. Put the thermostat in, bolted it up minus the one that broke.

Here is where the problem lies, when I went to fill the radiator to initiate my bleeding process, I hear coolant
come from under the car, but it seems to be dripping where the power steering rack is - are there any coolant lines or anything around there or above the rack? It seems like once I fill it above the middle of the expansion tank, it starts to leak. It was too dark and i couldnt locate it. So, now I turn on the car to try and bleed it and it goes to 12 o'clock in about 5 minutes - yay! However, with the heater on full hot and 4, there is only cold air blowing. I let it run for another 10 minutes before turning it off (Still no heat, not even warm air), but I did notice that there was no pressure or very little pressure/coolant on the upper radiator hose, but got hot, and the lower radiator stayed cold. I also noticed steam coming from the bottom of the newly put (missing one bolt) thermostat housing.

So my questions are; can one missing bolt from the thermostat housing cause overheating problems? Why is there coolant leaking around or above the power steering rack - any coolant lines there? Why is my heater blowing cold now? Any input and info will help a lot!! Thanks!

Sorry for the bad news but the broken bolt needs to be removed and the t-stat re-installed. It will leak...Try a easy out or take it to a professional. You car can not be reliable with a broken bolt on the t-stat cover.

Sorry for the bad new...

Also leaks will travel and drop at odd points, t-stat leaking could travel down the block and be blown over by the fan then drop by the PS pump. There are two hoses by the power steering pump. Heater down low (small hose) and top raditor hose off t-stat on top or a radiator leak from bad holding tank...


Best, John S

ok, thanks John - I have to look at it when it is day time and when I have a few hours to spare. It is leaking by the power steering rack, not the pump, almost by the tranny area. The thing that has me stumped is, it starts to leak when i fill coolant pass the mid point of the expansion tank - any idea on what would cause that?