75ZT Community

This thread isn't about me, but a Member on the other Club, who I fitted a Fan for today.

His CDT is racking up to 115 - 117 Degrees. There is no inline stat, the Coolant level appeared normal in his Tank. His FBH (Fuel burning heater.) was making Whirring noises though, randomly with ignition on.

Is it a possibility that the FBH is sticking on? Could that be a cause? Or is it likely the OEM Stat is stuck shut? There is heat from the Heater Blower, so Airlock in that area is not a likely suspect.


The fan is working, with a Gold Resistor etc.

Any help would be really appreciated

Carl.
tell him to disconnect the FBH and see how it runs then, if it does not over heat then you have found your problem, also was it over heating before you fitted the two speed fan with gold resistor it came to use in the end then

He may have an air lock get him to bleed the system if he suspects this, his he close or did he have to travel Arctic.

If the FBH was running, it would whirr all the time, plus the exhaust pipe would be red hot, and you'd smell it. So I doubt it's that.

The Engine was smelling of Hot Coolant when he arrived at my house, he didn't mention if it had done it before that, so I assumed as it was a 70 Mile Journey for him, it was down to the lack of Fan. Stupid of me really, I should have had a look whilst it was on my Drive.

He had had some Coolant removed as it was overfull apparently, He did mention that someone had used a Vacuum type device as he said they "Sucked" the Coolant out.

How old was the car? How many miles has it done?

One possibility if it hasn't been changed is that the water pump has failed, where the plastic impeller has decided to separate from the shaft. BMW had this problem in the early 90s and hence most BMW owners replace older pumps with ones that have a metal impeller.