My Xj has been overheating and i want to be sure of what the problem is before i start throwing money and parts at it. It overheats very slowly, even at freeway speeds it will overheat.When stopped at a light, if you rev the engine, this seems to make it go slightly cooler. Its had a new thermostat and new coolant tank and cap put in, as well as the coolant changed, and it still does it, however not as bad as before. I dont want to put in a new water pump and find out that it was the rad that was the problem, or vice versa. any help? also, both fans are working
Could be several different things. Does the electric fan come on at all? Make sure that works. And it could very well be the water pump. I have heard of the vanes inside rotting off and the pump doesnt leak, but it won't push the water like it should. Maybe a blockage in the radiator.
Does it have to be hot to check the clutch? Im not driving it right now cause of the overheating? I checked it just now, it was cold though, and it felt like there was a fair amount of resistance. The electric fan also works
I had the same problem with my 88. I chased the problem and fought the plastic tank war until I finally broke down and converted the system to a conventional open system with a new radiator. Once I did this all of my cooling problems went away. Well worth the money.
If i planned to keep it for a while i might do this, however, i am going to sell it as soon as i get it fixed, so i just want to spend as little as possible on it. Im selling it so i can put a new engine in my YJ
I also have an 88 and i have had my share of cooling problems. When water pumps go bad, cant you usually hear them? Are you loosing any coolant? any spots when you get into your car in the morning? but i think it sounds like your aux fan isnt kicking on.
97 XJ 4.0 Auto D30/29 Sp. 8.25. Yukon 4.10's
4.5" IRO Long Arm Kit - 33x12.50x15's
HD Offroad Engineering Shackle Relocation Brackets
Bilstein 5100's - Magnaflow Exhaust.
it was for a little while making a noise that sounded like a belt slipping, but it has been parked for a bit, and when i started it up the other day the sound was gone, so that is possible. the coolant in the tank looks mostly green, but at the bottom of the tank it looks kinda brown, so maybe thats a problem?
FWIW XJ's are notorious for overheating, the stock cooling system is barely adequate when new. So, you are probably looking at replacing most (if not all of) the cooling system to keep things cool. I replaced all of mine and eventually went to a 180* t-stat which made a bigger difference than everything else combined. I read a lot about gas mileage dropping with the lower temp t-stat, but that hasn't been the case so far(about 1.5 yrs now) the only side from the 180* t-stat is that my cherokee doesn't overheat anymore.
Sounds like you're losing pressure in your closed system to me, I was having the same problems with mine and it was that stupid coolant tank, I know you said you replaced it and the cap but are you sure that the cap is on nice and tight? Are you seeing any boil out anywhere or any leaks at all? If it is getting that hot truly then you would see some type of boil out or something somewhere. I would also look into maybe replacing your temp sending unit to make sure that it is properly functioning. I just went to pick n pull and grabbed all the parts i needed to swap to an open system, since it was over new years they were having a 50% off sale and I did the entire swap for around $80.