UAEOffroaders

does it over-heat anyway or just when its moving?
if only when its moving , on road or only off road?

Assuming that everything else is okay including the block gasket and overhead block itself, she should install original Jeep Electric fan, it is costly, something over AED 1,000/-.

Khaled - she says only when off road (and also when left running for a long time during the RTA test) - I will check with her later on any other symptoms or description of when the problem happens.

Thanks for the help guys.

ask her to check the water level in the morning, if her car keeps having big amount of water shortage she has to rebair the block gasket or overhead block itself, other wise it is just an electronic problems wih the fan or the hoses, i had the same problem before with the same model

Nobody has thought about the water pump or fan clutch yet?

The water pump is driven by the same drive belt as the power steering pump, and the fan clutch is attached to the water pump's pulley so this could explain why it may be overheating when turning one way for a long time. It may be that the belt is loose and when being put under pressure, it's slipping. It could also be the viscous coupling in the fan clutch being worn out as it is heat activated (if a mechanical fan) and it may have become old and not engaging fully.

Has she checked all of the pipes, gaskets and radiator for leaks?

If she has two fans (electric and mechanical) it could just be that one of them is failing/has failed. Ask her to get somebody who knows how to jump the wires on the electric fan to see if ti activates the motor. If not, that's your culprit.

Good luck

Many thanks for the advice folks - I will let her know

Also mate, ask her if she has only an electrical fan. If it is, it should have two speeds. If the high speed is gone it could be that as it will only cool up to a certain temp before the high speed should kick in. I had a similar issue on my ZJ. It was perfect when driving at normal road speeds, but once I slowed down or stopped it would overheat.

If it's a two speed fan, it should have three wires in the harness, two for a single speed fan.

A stock XJ has one single-speed electric fan and one viscous clutch mechanical fan.
If the engine only overheats when the Jeep is at a standstill or just crawling at slow speed, it's likely that at least one of those fans isn't working properly. The electric fan should come on automatically when:

a) You switch on the AC or the defrost.
b) When the coolant temp. gauge reaches ~105*C.

The clutch fan should spin quite freely when the engine's cold but have some resistance to spinning by hand when the engine's hot. If it spins freely even when the engine's hot, the viscous clutch is shot.
If the engine also overheats at highway speeds the hot favourite (pun intended) is a clogged up radiator. Sixteen years' worth of limescale and silt won't come out with a flush so if the radiator is still the original one, it's time to say masalama.
Water pumps usually leak from the weep hole long before they fail and when thermostats start to fail, a coolant temp. that rises quickly to halfway (or higher) after a cold start is the first sign.
Jeff, send your friend over my way and I'll diagnose the problem for her in no time. After more than 18 years of XJ ownership I know an XJ like the back of my hand.

. After more than 18 years of XJ ownership I know an XJ like the back of my hand.

Hey Dino, when can I make an appointment? my xj 99 is in need of a doctors opinion or maybe not. Could you have a look at her as well?




Mosalf 0566161157