I just bought an 86 mustang, it has a new radiator and dual electric fans. When driving it will get to the ] of [NORMAL] and then i shut it off, afraid to overheat a car i just bought. Could it be a bad thermostat? Rad and resevior are both full of coolant, and i know the factory guages arent worth a damn but it still shouldnt get that hot to begin with. Please Help me out.

 

Don't be afraid to overheat it. If the coolant is topped off and your still in the normal portion of the gauge you may not have a problem at all. Just keep an eye on the gauge and don't let it run to far into the hot portion of the gauge.

 

Use an infared thermometer to check actual temps, I bet you'll be surprised how far off stock gauges can be, as you know. Then compare that to where your gauge is reading. The "L" in normal might be 180'.

 

Stock gauges are junk, if you have some extra cash I would recommend buying an aftermarket gauge with actual numbers. Could just be the gauge sender going bad.

How are he fans wired? Are they dual speed? Maybe the slow speed is all that is cutting on and not providing enough cooling force to the radiator. Are you positive it's even coming on?

 

I have them hardwired to a toggle switch, they are one speed and both on at the same time, i just drove it about 15 miles in stop n go traffic in 80 degree weather and coolant was purging out of the overflow. The needle has usually passed into the red zone when i drive it a little while

 

First you need to either wire them to come on only while the car is running or get them wired to a temp switch. Next what is the model of the fans or what did they come out of. They might not push enough air as required by your motor. Can you post a pic of how it's mounted to your radiator?