Cooling issues

saintpcr

New Member
Messages
8
Likes
0
Location
Florida
#1
I have a 1996 328i. The other day it started overheating and steam was coming out of the radiator. The check coolant light kept coming on for months but everytime i checked it there was coolant in it. I checked it the day before it overheated and there was coolant in it. However after it overheated and cooled off i checked it and there was no coolant in the reservior. If anyone has an ideas or has experienced a similar problem let me know. Thanks.
 
Messages
4,917
Likes
18
Location
Reading,PA
#3
You may have a slow leak. Big Daddy's right, you need to bleed it to diagnose it any further.

I just replaced the radiator, expansion tank, hoses, belts, idlers on my 94 so I'm very familiar with this right now. The Bentley manual says:
1. Fill the expansion tank to the cold level
2. Open the air bleed screw next to the cap.
3. Turn the Key to the ON position but DO NOT start the car.
4. Set the heater controls to full heat with the blower on.
5. Fill the expansion tank until no bubbles come out of the vent line.
6. Close the air bleed screw.
 
Messages
4,917
Likes
18
Location
Reading,PA
#6
The procedure I listed above is the initial fill procedure per the Bentley manual, after you have drained the system. It will get most if not all of the air out of the system because the bleed valve is the highest point in the system. If you start the engine to add coolant before the level is high enough, you wind up pumping air into the engine because the impeller is not fully submersed which just makes the problem worse.

The procedure has you fill the overflow tank COMPLETELY to the top, well above the KALT/COLD normal fill level. The extra coolant is intended to displace the few air pockets that might exist.

You still need to start the engine and check the levels, bleeding if necessary, AFTER doing the procedure I mentioned.
 


Top