Help! Overheating problem with my 1988 325is.

[bmwdt]

hey guys...

so i was driving home yesterday from langley and my car's temp started to climb. turned on the heat and it kept climbing. it stoped and stayed constant just below the red.

as i start moving from a stop the gague drops to 3/4 but then goes back up.

just wondering if anyone has had similar problems and can help me diagnose it.
I will run it tonight after work to see if a can provide any more information

thanks in advance

derreck

[craig4ie]

Are you stuck in stop and go traffic, or are you moving at a consistant speed when the car heats up?

Is the car leaking, do you have enough coolant?

[bmwdt]

coolant level is good. it overheats on the highway and in stop and go

[craig4ie]

Well if that's the case then I'd say that coolant isn't flowing like it should be.

You might have an air bubble in your system, a plugged hose or a cooked waterpump...

If I were you I'd replace the waterpump and thermostat, then flush the coolant system.

[320Colin]

Originally Posted by craig4ie well if that's the case then i'd say that coolant isn't flowing like it should be. You might have an air bubble in your system, a plugged hose or a cooked waterpump... If i were you i'd replace the waterpump and thermostat, then flush the coolant system.

+1.........

[ClassicScot]

+1 thats a problem i had as well

[DS Rook]

Does it actually overheat or does the gauge just read HOT?

[Slammed80]

Had a similar issue with my 318is, turned out to be the thermostat

[bmwdt]

"Does it actually overheat or does the gauge just read HOT?"

sits a hair below the red

[bmwdt]

Originally Posted by DS Rook Does it actually overheat or does the gauge just read HOT?

it sits a hair below the red

[Rhys]

could just be the thermostat getting stuck closed(like slammed 80 said). I had the opposite problem on my M42, turned out the thermostat was getting stuck open, so my temp guage would fluctuate between the top of the cold mark and just below the halfway mark. Check out both, if its the thermostat it will be cheaper, and you wont have to drain your cooling system.

[bmwdt]

so...i let the car heat up, felt the all the hoses, and there was a definite blockage before the thermostat.

i switched it out... it took 10 min... and was back driving at a perfect temperature.

thanks for all the input.

[M635]

Your going to have to flush the entire system out. You know that little screw on the the thermo-stat? Open that up a bit. You will hear some hissing, and air bubbles forming, until eventually you will see coolant oozing out. Don't open it too much though!