Advice wanted (repeat from project thread)

[Dobby84]

when did the fan run last?

Hard to tell really, Ive had it out with the rad quite a few times over the last few months. I guess it would have been when I installed the catch tank. Ive checked the plug in the back of the motor and its okay, checked the fuse in the fuse board too and its also okay.

If the fan doesnt kick in would it cause the pressure to get too high? Please note that the temp was below 90 on the clock during the sniffer test when it boiled over.

[mcandmar]

Boiling point of water changes with pressure. The higher the pressure the higher the boiling point. So running without a cap on the system it will boil over very quickly, the system has to be under pressure. The cap is also designed to vent over a certain pressure, so unless it is leaking dont worry about it.

Have you checked the temp sensor is plugged in at the bottom of the rad, i have forgotten about that myself

As s2driver says, bridge the connector to confirm the wiring and Fan are all working, failing that i would remove the sensor and test it.

[pasbogdan]

Try reving engine with the colant cap off.Do not try that test with water at 90.
But also to cold engine will not show anything if there is a crack because it expands at heat.
When i had a broken gasket when i was reving,the cap at water tank made a whistle.Also with the cap opened there were lots of bubbles when reving.

[Dobby84]

The sensor is plugged in but I havent checked if its working yet, not really sure hoe, electrics aren't my strong point if im honest.

Im going to put 12v across the fan to check its working too.

The test wasnt performed at 90 but around 80ish so the stat was open. Im not getting any bubbles when im reving the engine. just coolant, hard to tell though as its so hot.