yep................overheating!

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R reg 993cc hijet. Can anyone tell me where the radiator fan switch is? ....fan switches on, but not very often.
Also would like to know whereabouts the thermostat is..........think i found it......is it just a valve? are they prone to sticking/breaking?
Thanks for any help

1995 Hijet 993cc overheatting -

I am having to replace my headgasket due to overheatting problem I had similarly where the temp would go right up then drop after starting to boil over, I thought I would wait to fix it in the spring!
What I should have done was think it through.
Water loss from coolant system (pressurised system for maximum heat transfer):-
1 Check hoses
2 Check rubber gaskets on Rad caps ( two - one on the radiator and one to allow over flow into the reserve tank)
3 Bleed air from system (including heater matrix bleed nipple above rad under front cover.)

I did the bleed but not the checks!
It turned out to be the pressure cap at the overflow bottle was allowing the water to escape before pressure had built in the system to the right point.
This water loss led to a melt down and overheat the gasket and blew it. No oil in the water, no water in the oil! strange... while I waited for new pressure cap I used some rubber to seal the old perished cap it worked but then found steam exiting from the exhuast pipe (place cloth over exhuast pipe and see/smell for steam like when you iron your shirts etc.)
This I knew to be a sign of blown H gasket Sad and then found water in the oil (emulsion) so ordered a new HG and as there are only partial workshop texts available have done what any unemployed guy would - got my hammer out! Hopefully if all goes right I should be back on the road by next week (gotta find my torque wrnch now)

Moral of story - make sure your coolant system is a sealed one, loss of water = bad news. My garage qouted £700 for HGasket replacement and I would have to wait 4 weeks for imported gasket.

I have taken lots of photos as I have stripped the engine to help in rebuild hopefully I wont forget to check for coolant leaks. - 1995 993cc s85 cb42 Hijet

As for the fan it may only be switching on when hot water gets to it, loss of water will cause air pocket to form and wont trigger the switch or the thermostat etc...
Thermostat ontop of engine at back - under bolted down hump behind seats.