Can anyone advise?..

I was out practicing this afternoon when I noticed coolant spitting out of the radiator overflow pipe...

The fan wasn't running which I though was strange - when I got back I put a meter across the two pins of the plug that feed the fan - the voltage was 8.5volts and climbing up to 10v. I plugged the fan back in and it was running fine?..

I went back practicing and it happened again - I had the meter with me again and this time it measured 2v?

I've read a few other topics on here which sound similar and it seems like it might be worth connecting the temp sensor wires/pins together and try to run the fan all the time??...

If this works it is the temp sensor? If not chance are the rectifier?.

Any advice would be great fully received

Cheers

Check the water pump impeller by draining coolant and taking off cover, easy job. This happened to my mates evo. We couldn't work out what the problem was until then. The impeller blades were sheared thus coolant was not circulating effectively. Just have a quick check to rule this out if nothing else. Don't ignore this as if this is the problem, your fan running constantly won't stop the overheating

Thanks for the advice Dave - finally sorted the issue - the thermostat/temp switch in the radiator had failed.

Swapped it and now working fine.

A word of warning though I was sold a sensor labelled as 2010 EVO and assured it was identical to my 2013/14 model...

It wasn't, confirmed by BETA UK - the wires are a lot shorter on the 10-12 models than the 13/14 so had to rewire it.. works fine now but a bit of a pain...