hello!fellow thirg gen owners.new to this forum and asking for help.im a proud owner of a 1985 iroc z28 305 tpi.just got the car about two months ago all stock with 96,000 original miles and im having issues with the radiator fan.when i got the car the fan would come on as soon as i turned the key and now it does not come on even when the car is on and running.i have replaced the relay and no answer.could it be the temp sensor or the fan motor?also the car has no a/c.any help would be really appreciated.thanks!

 

Someone will correct me if I am wrong, but usually the fans on these cars are controlled by a sensor on the block and I believe the stock one is around 200 degrees to turn on. This question might be better answered in the cooling section of the forum.

 

Do you have 1 or 2 fans?
To see if it's the fan motor, you can jump the relay if doesn't run check the contacts at the fan if it still won't run it's the motor.

 

also check the wire plug as the fan temp switch located on the passenger side head as stated, sometimes they fray, or the plug breaks due to the ehxuast heat. might be a goo idea to replace temp switch anyways with a cooler on/off setting. stock i believe is 225 on.

 

 

Wait till you need to rebuild it then go 350. The only thing I'd do to a 305 is chip it IMO.

 

headers on the 305 will be fine on a 350.