Help! My car is overheating fan isn't kicking on

[87vettevert]

Well I just fixed my clicking noise by replacing the u-joints...but the first ride i took after taking to car off the jacks I noticed the low coolant dummy light on and the car was rising in temp. I opened the hood added a little bit of antifreeze. Then i took it for another ride and it was still getting hot...opened the hood and noticed the fan wasn't coming on...any suggestions?

 

[rlg]

just a guess , check the fan relay.

my coolant light came on also.

the over flow tank was empty, to be on the safe side I let it COOL and filled it at the tank on the fire wall. then I added some to the overflow.

light never came back on.

 

[Bob Chadwick]

What's hot? People complain about the C4 running hot all the time but the fan is not triggered to come on until the coolant reaches a temperature in the mid 230's or so. I'm sure someone will chime in with the exact number.
---edit---
I did a quick search in the C4 section on Fan Temp and came up with some posts that might giove you some information. I don't know if the 87 is differerent but according to this post the fan doesn't come on until 234 degrees. Anoyther post I saw said 228 for the 88.

http://www.corvetteactioncenter.com...ce/107635-aux-fan-not-working.html#post916934

http://www.corvetteactioncenter.com...22-whats-normal-temp-range-my-1988-vette.html

 

[black_81_vette]

You could wire the fan direct and see if its working, or change the the sensor in the head to turn the fan on sooner. I wired mine up to a adjustable switch with a thermocouple so I had controll of when the fan came on and off.

 

[bucket]

i also have an adjustable relay...end of problem
factory fans dont come till around 210
and it"s not "HOT" till it gets to 250...according to bowling green
i dont accept this
also use an additive in your coolant..watter wetter will lower your temp by 10 degrees

 

[vetteoz]

change the the sensor in the head to turn the fan on sooner. I wired mine up to a adjustable switch with a thermocouple so I had controll of when the fan came on and off.

Switch in drv side head only controls aux fan WHERE fitted. Main fan controlled by ECM from CTS signal.To change the on/off temps on main fan need chip reprogrammed unless to you do manual over ride

 

[hdcwagsvette]

Most likely the relay. Take a look at it by the battery you will see right away if it is melted like mine was. After I replaced it the fan worked fine. It kicks on around 234 if I remember correctly.

 

[redvett]

This is out of the 1987 service manual.
Fan on @ 226F controlled solely by the ECM.
Fan on with A/C refrigerant pressure 233 psi.
Fan off vehicle speed over 35mph coolant temp below 234F @ A/C pressure below 233psi.
This also covers up to 1989 model years.

 

[bucket]

those numbers are , of course, factory correct and accurate...
i dont subscribe to that theroy.
so...opinions vary