I installed the Perma Cool fan control kit. I have it set to turn on at 160*, I have the temperature probe in the radiator on the passenger side about 2/3 the way up. (the passenger side is the side that feeds the block?)

I don't understand, sometimes the car will warm up and hold 180* fine. Other times it will just sit at 220*.

For example, today I was timing my car, I went outside, started the car and went about my business. Before I know it, the temp gauge is reading 240*, coolant starts blowing out a hose (I'm assuming it started to boil) and my fans are not coming on. I shut the car down, then I put the key in the ready position, the fans turn on. I start the car, and the fans turn off. I shut the car off and then put the key in the ready position and the fans don't turn on. I take out, then put it back in the ready position and the fans turn on.

I don't understand, the other night the engine was at 220* and I'm getting mad because thats way too hot. I got out of the car, popped the hood, the fans were running. Eventually the temperature dropped to 180*.

Is my temperature probe on the wrong side or in the wrong position? I just don't get it because sometimes I can drive extended periods and it will NEVER go above 180*. Other times the engine goes to 220* before the temperature drops back down. I've got almost 11:1 compression on this engine, 220* isn't going to cut it, I'm on the borderline for pump gas as it is.

It just seems like the fans don't always turn on when they are supposed to. Sometimes they come on and sometimes they don't. Do I have a defective control unit? I am just very unhappy that my engine went to 240* today and the fans did not come on at all. I suspected the temperature unit wasn't working right when the engine would sometimes hold 180* and sometimes not, but the fact that it did not turn on even though my engine was at 240* means something can't be right.

 

I have flex-a-lite dual fans with temp controller.My temp sensor probe went in the top radiator hose opening.Its worked fine.Sure you have yours in the right spot?