hi guys i recently brought a 1994 jeep cherokee that had a few problems when i brought it..
it runs a dream except i found out that at idle , the temp gauge rises over half ..now the strange thing is it dosent do it all the time.its not overheating but just sits at the white line before the danger red zone at worst,but drops once im back driving as usual. so what ive done so far is changed the thermostat and the housing .brand new radiator and new coolant right thru..it still does it just not as bad..now ive been looking at the water pump and im pretty sure its ok but cant rule it out..it dosent use any water or oil either..my guess..(and its just a guess) is that it may be a faulty sensor thats playing around??? i dont want to change the water temp just yet incase its somethiing as stupid as changing the temp sensor sender for instance..
now i no this topic has probaly been discussed but new to here and just wanting a bit of direct help..
cheers

 

what engine do you have? Is the fan clutch doing its job? get your hands on a digital infred temp gauge and take temp readings at thermostat housing. are both heater hoses hot,you can carefully take one off and start it preferbly COLD and see if coolant is running out. if coolant is running the pump is pumping.
typing isnt my thing but hope this helps!

 

Sounds like a fan clutch issue, they're about 50 bucks for a heavy duty one.

 

yea have suspected the fan may not be doin its job as its only kickin in after the temp is a bit over half way.so what would be causing this? the fan itself or is there a control box or something ??

 

The electric fan will kick on when the temp gets to 219 degrees, or anytime the A/C or defroster is on. The belt driven fan has a viscous clutch that relies on heat to engage it. If the spring on the front is broken, or if the fluid leaked out of the fan clutch, or if it's just worn out, it will not work as efficiently as it should.