NewJerseyXJ609

Hi... i have a 95 xj with the l6 HO... its got 186k miles on it and runs like a champ.. the only problem with her is thatnwhen i come to a stop.. or am rnning slow speeds it heats up... not into the red.. but just before it.. it has never throw fluid.. and doesnt have any loss power... the top radiator hose gets hot.. could this be a bad tstat? i just replaced it about a month ago... any suggestions would be apreciated...
chris

EDIT... forgot to mention.. when i continue on the road... say from a red light.. it cools back down.. and temp sits below 210.. it just at stops or slow speeds is when it heats up.. elec fan kicks in.. everything seems normal.. but temp guage goes up way more than i would like to see

bishop letov

theres been a few threads about this sort of thing. use the search and youll see tons of overheating issues. Also youll see about a dozen resonses that will give you a heads up.
getting hotter in traffic is something that these jeeps do. How hot depends on a few things. you say its not in the red so my first suggestions would be to check the fan clutch. when its cold you should be able to turn it without too much force. When the engine is up to operating temp it should be a bit harder to turn if not stationary.

Check the fan shroud and make sure its seated properly as well as you electric fan.

Did you flush inside your rad really good and make sure the fins are cleam and clear of mud and bugs?

You stated that you did a thermostat change. Did you burb the air from the system? Some people do this by loosening the temp guage idiot light sensor at the rear drivers side of the head. Some park nose up on a hill and open the rad cap.

A slight increase in temp is going to happen. but you never stated from what degree to what degree your varying from.

you can test the t stat by taking it out heating it with a propane torch without touching it with the flame or putting it into a pot of water and boiling it till it opens.

Dan4governor

also, you should know that all engines run hottest at idle. this is due to the fact that when you are revving the engine it is rushing in new coolant from the radiator and pushing the hot air out of the exhaust faster, while sucking in more cool air. as long as you're not in the red you are fine. if it really bothers you, check your engine fan clutch. my money is on the fan clutch.

NewJerseyXJ609

thanks... it goes from sitting at 210..200.. then goes to right before red i would say 240... some people tell me this is normal for this engine... it runs so good.. even with almost 200k.. i dont want to harm it anymore i dont know if i should let it be.. or cool it down.. i was told putting a 180 tstat may do it.. but the engine calls for a 195 t stat.. correct?

NewJerseyXJ609

the fan clutch should have no play in it at all.. by thgat i mean side to side.. it has a little bit of play.. and who knows if it has been changed in the longest.. after all.. i just picked up this xj about 4 months ago

NewJerseyXJ609

ive taken the rad cap off.. let it warm up.. until the it starts to over flow out of the rad... thats what ill do to fill it up with coolant.. would that be sufficient bubbling? all the bubbles come out.. excuse my newbness.. ha

bishop letov

We all started new at some point..

The engine should be off when you tak the cap off after it has cooled a bit. then you finish filling it with coolant and recap it. Whatever the cooling system cant fit at that point when the coolant expands from heating up will go the the overflow bottle..

Burbing is just the term for getting the pockets of air out of the system so you dont have air sitting in the head. If you leave the air in there it causes hot spots and when the coolant hits those hot spots it turns to steam thereby not effectivelty cooling the head like it should.

one last method to "Burb " the system is by sqeezing the rad hose a few times to force coolant into the engine and youll notice more room in the rad to fill it. sometimes it will allieviate itself.

Just check the fan clutch and use whats posted apove for refrence like " no side to side movement" and at temperature it should be hard to turn with the engine OFF.

Keep the questions coming because its the best way to learn.

Dan4governor

your t-stat is fine. it's obviously working, and no, a 180 t-stat won't help this situation. a 180 t-stat will only make it so you engine warms up slower when you first turn it on. it actually isn't a good upgrade to a 195 t-stat because your engine is made to run best at 195-210, if it runs cooler than this it is actually not very good for your engine.

NewJerseyXJ609

yeah if it runs cooler that robs gas mileage i hear.. im going to check the clutch fan today when i go out.. ill let you guys know... thanks for all the help
chris

bishop letov

the 180 t stat causes it to run in warm up mode and richens the mix and keeps it like that longer.