Rad fan cutting out

[Jordk]

I fitted an 8" fan to my half rad on my starlet and run it through the standard fan wiring. The fan runs constant on ignition. I've heard this is common and not much of an issue. What I'm finding is that it stays on and is fine until it's up to tenperature (more so after I've moved it around the units I keep it at) that the fan cuts out and the engine starts to overheat. Is it possible that there's something up wiring wise? Or that the fan motor just isn't rated to run constant and cuts out due to overheating of the fan itself? I have a larger 10" fan I was planning to fit instead of there's a fan issue.

[Gary91]

Could it be the wires the wrong way round, if the fans cutting out when it should be coming on? Have you still got a plug for aircon next to the passenger headlight? I plugged in the sensor so that my fan would run all the time. If its a universal fan from ebay, it should be able to run all the time.

[Jordk]

All swapping the wires around does is reverse the polarity thus making the fan spin the wrong way/in reverse pushing not pulling. I never had air con to start with the previous owner removed it. Worst case scenario I'm thinking of just running it off a 12v constant feed on a switch. Good idea?

[Stu]

Might pay to check how the fan relay and the triggering is wired up, is it still the stock unit? Just sounds like its switching the wrong way - from memory the stock EP82 triggering side of the relay is setup as absence of earth = fan relay on (ie either sensor up to temp or unplugged) and EP91 are the opposite. Could be that the sensor is a EP82 unit (cuts earth when up to temp) but its running to a EP91 relay which would mean the fan works in opposite and stops when its at temp.