1991 525i overheating issues.

We drove our 1991 from San Mateo to Palm springs without incident, drove like a dream. Today we went out shopping and after about 7 miiles the coolant temp warning came on, and the temp needle was at the verge of entering the red zone. We pulled over and let it cool down to half way (the coolant bottle was full). We drove home with the heater in the cab full blast and that got us just about home before the coolant temp warning came back on. I held onto the radiator fan when it was hot, and had someone start the car and there was no real pressure in the fan wanting to spin,. I mean if I let go of it, it would spin but I could stop it with my bare hands and hold it in place with one finger. Does that sound like our fan clutch is shot and needs to be replaced or is that normal for a car that is hot?

Thanks,

Reply to
GamePlayer No. 1058
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A bad fan clutch is only a problem at town driving speeds. If it overheats above 30-40mph you have a dead water pump, there's a design fault in M50 water pumps.

Reply to
John Burns

are the water pumps on these vehicles like some others in that when they go bad they leak out of a weep hole? Because there is no leak on this one.

Reply to
GamePlayerNo.1058

It has a plastic impeller on a metal shaft, they part company eventually.

Reply to
John Burns

Okay, turned out to the the thermostat, it was basically in two pieces, the shop replaced it and the fan clutch (because it was weak) and now the car doesnt overheat anymore.

Reply to
GamePlayer No. 1058

i would still get a new water pump as theses cars are prown to over heating if your going to do the water pump get a stat and housing aswell, you will also need to bleed the coolent system a few times whern you fill the rad back up with coolent, they have a tendescy to air lock when you do a water pump

Reply to
Shane Ward via CarKB.com

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