86 corvette with 65, 00 miles
When the coolent temperature went over 235 and kept rising I stopped and the coolent fan was not running. I truned the car off and as I twisted the key off the coolent fan came on. I imidiately started the car and the coolent fan came on (the temperature was now 255) the fan stayed on long enough to bring the temp down to 210 and the fan went off. It did not come on again and the temp went up to 260. I shut the car down again and let it sit for approx 5 minutes. When I started the car the fan came on. As I let the car idle the car will start to get hot (235 +) and the fan goes off. Sometimes it only stays off for 30 seconds, but other times it stays off for a couple minutes. I have installed an aftermarket low temp sensor to bring the cooling fan on at 200 which work well, but when the temp gets hotter the fan stops. I have installed a new relay, but that did not help. Could the fan itself be bad?
Yes it could be. Is the temp. Control in the fan or on the engine? If it is on the engine, and not on the fan, get a jumper wire, and connect from positive side of battery to side of the switch that goes to the fan, if the fan is good it shoukl work fine, and for as long as it is connected that way.
Also check to see that the fan has a good ground. The grounding has a lot to do with the electrical equipment fuctioning the right way.