M20 over heating issue

[bmwguy325is]

So as mentioned above you need to check the fan. The one attached to the water pump pulley. The main fan is powerful enough to cool the car properly at idle.
However if your AUX fan never came on than it as well is fouled up.

[Shahriar35]

I believe it is the main fan. Did the roll of newpaper trick.

Where can I get a new fan clutch from for a decent price and quicky? Autozone wants $92.... A bit pricey. I would like to get one tonight. Thanks

[SmokeE30]

If you current mechanical fan passes the news paper test it would be safe to say that it's probably ok however you said turning the ac on to activate the aux fan cools it down so it could be a contributing factor. You can get a new fan clutch for around 50$ online but idk what stores In your area may have one available tonight

[603Racing]

Sounds like a bad fan switch. That may not be why your car runs hot though. Like e30Gus said, could be fan clutch or water pump.

When was your timing belt done last? Maybe time to go ahead and do a t-belt/water pump job.

[fatsooo]

When was your timing belt done last? Maybe time to go ahead and do a t-belt/water pump job.

Hopefully the t-belt and water pump was one of the first things you did when you got your car...
But anyways depending on where you are in CA, pelican parts and bma have fan clutches for like 60 - 70 bucks and should get to your house next day if you order early enough. I'm in OC and usually get my parts delivered next day from both suppliers if I order early enough.
Turner has it for a but cheaper, but takes a week to get delivered usually.

If you're a stickler about your cooling system like I am, I would test that aux fan too. My switch went bad and its like $30 $40 to replace with new gasket ring too

Sent from my SCH-I535 using Tapatalk 2

[Shahriar35]

So here is the update:

I did the fan clutch and it helped greatly, the new one of course passed the newspaper test. Now the problem is that it doesnt get cooler than 3/4. After the car is warmed up, it remains that high. As for the AUX fan, it never kicks on....

[jlevie]

So here is the update:

I did the fan clutch and it helped greatly, the new one of course passed the newspaper test. Now the problem is that it doesnt get cooler than 3/4. After the car is warmed up, it remains that high. As for the AUX fan, it never kicks on....

Is that the gauge reading when driving at 45mph or greater? As a recap, at this point you have replaced the thermostat, fan clutch, and radiator with new, not used parts. Right? That being the case, I'd want an independent measurement of head temperature with a contact or IR thermometer. With the OE thermostat you should see ~176F.

At speed the fans aren't what cools the engine, though they are important at low speed or when idling. The air flowing through the radiator does work.

[Cephas]

That being the case, I'd want an independent measurement of head temperature with a contact or IR thermometer. With the OE thermostat you should see ~176F.

I would definitely check the temp with an IR gun. I went through a similar problem on my car and it ended up being the nut on the back of the cluster. It was loose and my temp gauge would creep up to the 3/4 mark. I tightened the nut on the cluster and voilà, problem solved!

[Shahriar35]

Is that the gauge reading when driving at 45mph or greater? As a recap, at this point you have replaced the thermostat, fan clutch, and radiator with new, not used parts. Right? That being the case, I'd want an independent measurement of head temperature with a contact or IR thermometer. With the OE thermostat you should see ~176F.

At speed the fans aren't what cools the engine, though they are important at low speed or when idling. The air flowing through the radiator does work.

So if the head temperature is around 176. What would the conclusion be? A issue with the gauge/cluster?

[Shahriar35]

I would definitely check the temp with an IR gun. I went through a similar problem on my car and it ended up being the nut on the back of the cluster. It was loose and my temp gauge would creep up to the 3/4 mark. I tightened the nut on the cluster and voilà, problem solved!

Which nut was it on the back of the cluster? I may check into that. Thanks

[Ceeker]

the nut behind the temp gauge loosens off in some cases creating a false reading on the temp. tightening it down will correct the problem. caused by time and vibration. put some loctite on it and you're done.

[Shahriar35]

I just wonder if that is what my problem is. I just need to get my hand on a IR thermometer so I can see if my head is at the right temperature.