Hello All! Brand new to the boards here, so first I would like to say, glad to be a part of the community! I finnaly was able to scrape up the funds and purchase a 1987 IROC this week! My problem is with the cooling system. My engine seems to be running hotter than it should? When stuck in traffic, it will tend to get up into the 230-240 range. It has never actually made it into the red. Upon investigating, I found that the fan on the drivers side, will kick on at about 230 degrees, (even with the ac off), but the passenger side fan will not kick on? The fan motor is fine, so I assumed it was possibly the relay. I changed that, with no luck. I did however discover that I can activate the relay manually, and the passenger side fan will kick in. When I activate the relay manually, only the passenger side kicks on. Are the two fans on seperate relays? My next thought is the fan switch? If that were the problem, would my dash guage still be reading temp though? I would assume that if the switch were bad, the dash guage would not give me a reading, or is that a completely seperate issue? Any help you all can give me would be greatly appreciated! I am by no means a master mechanic, but am learning alot as I go along!
Thanks!

Jeremy

 

I think the "old" style fans had one hot, and one computer controlled. ie: 1 is always on when engine is on, one turns on to help cool... is that correct?

Anyways, if one doesn't turn on, try a hot to it and see if it is dead.

But, even w/ 1 fan, you shouldn't run that hot. You will also want to flush your system... let the car set 3-4 hours and drain all of the antifreeze out, flush it a few times with water... even run it 1-2 mins and drain it again... i went ahead and got a "neglected" radiator cleaner deal... prestone brand i think for mine.

ScottieB

Also, make sure you use the *green* radiator fluid for our cars... the orange is not for our cars.

 

the fan switch and the gauge sensor are 2 different circuits. the gauge sensor is located under the driverside head between cylindars 21 and 2. the secondary fan switch is located under the passenger head by cylinders 6 and 8.
your fans are operating normally.
primary comes on at 234 i believe and the secondary comes on at like 2456 or when the ac is on.
most people believe this is to high so they change the fan turn on temps to about 170-180 or so by swithcing the sensors for both fans respectively.

hope this helps

 

Yes, this helps alot! I just read the tread done by "willie"! Very good info! I would never have expect normal operating temp to be that high! Thanks much to all! It is a relief, to have one problem out of the way! Now I can spend teh money on brake pads and rotors!!!

 

I have the same issue, but my secondary fan doesn't come on at all. Whether it's hot or if the A/C is on. The fan does work, ran 12 volts to it. Also swapped relays and that's not the problem. The electrical plug on the that goes to the switch was broken and cracked, so I replaced it. Should I try replacing the switch on the head?

 

it couldnt hurt to relace that swithc in the head.