Help!!! Overheating

[doughboy37]

I have a 1989 Jeep Cherokee Larado with the 4.0L motor in it and I have done everything but put a new radiator in it and overflow bottle, I have replaced the water pump, the thermostat and the thermostat housing and still the motor over heats within about 10 min of idling anyone have any suggestions that would help please before I tear the motor down and start over with the motor and go from there. This motor has over 200,000 miles on it but just reciently started this problem cannot go more that 20 miles before it blows a cork or run for more than 10 min at an idle before the motor starts to run faster and then overheat.

[wwwildman]

Ckeck your fan clutch. My 90 did the same thing. I thought it was the thermostat and replaced it but it kept overheating. Turned out it was the fan clutch and after replacing I have not overheated.

mike

[G.A.S.]

did you blead the air out of the system for starters. You said it overheats within 10 min. that is about the ammount of time it takes for the thermostat to open for the first time.

[AlohaBra]

Better have a shop check that radiator unless, it is less than 4 years old.

[mmcpeck]

Yeah I think I'd check that radiator before I tore the motor down.

Also as was mentioned, try bleeding it, trapped air will overheat it in no time.

[gtmud]

Overheating, get rid of the closed system all to gether and convert to an open system, I did this on my 89 and never had another problem! Get a rad for an 96 model year and purchase an controller for your fan. Adjustable thermostat to turn the fan on when needed. This will eliminate any heating problems.

[thundergod1320]

Provided you don't have a blown head gasket, I've found that pouring a bottle of Lime/Away or other household lime and rust remover into the radiator,(with the thermostat out) running it for about 30min, then draining and flushing it out will usually get you some decent flow in the cooling system. (leave the heater on too) It isn't as caustic as automotive chems and seems to work better than most stuff I've used. Yes... Make sure that the clutch fan is OK as well. They can give you an overheat pretty fast if theyre bad. Thermostat should be changed... theyre cheap and arent worth saving.