HI
I have an 89 firebird, and a couple years ago I dropped in a 350, and took off all the fuel injection and put on a carb.

I ran the radiator fan through a toggle switch.

this lasted about 30,000 miles.
the other day the switch burned out
I replaced the switch with a 25amp unit and 10gauge wiring, the switch lasted about 2 days and it burned out again.
I now am running a 30amp switch, but after 1minute of bieng on the switch and wire connectors get so hot I cant touch them.

when i turn on the fan, the voltage drops down to about 9volts, and the rpm drops, almost as if the AC compressor is turning on(it is not turning on) it also makes a very loud noise almost like a turbine spinning up.
the fan will rotate freely when spun by hand.

please help, im sick of driving around with the heater blasting!

thanks in advance

JL

 

check the ohms of the wiring and the fan motor. something is causing it to pull way to many amps. If this is all the sudden suspect the fan motor.

 

Totally agree, prime suspect is the fan motor itself. If it is shorting out it will still spin freely. You might also want to run through a relay vice straight wiring it to the switch (safety)

 

You definitely need to run a relay...the stock fan will draw over 25 amps during startup.

Pete

 

thanks for the help, fortunatley its a pretty cheap repair

JL