New thermostat and still overheating
#1
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New thermostat and still overheating
Have 91 jeep cherokee. Overheats in parking. Changed thermostat to no avail. Thinking is water pump. But I notice no water leaking from pump. Second radiator turn on when approaching red line, but still advances. If I turn on heater in defrost mode, or any mode no hot air. When i feel radiator top hose feels hot but can easily squeeze it. Any ideas?
#2
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Join Date: May 2015
Location: San Antonio, TX
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Year: 1992
Model: Cherokee
Engine: 4.0L H.O.
First a little more info would help.
-Have you verified the temp with an IR thermometer?
-What temp thermostat did you install?
-Have you done a thorough flush of the cooling system?
Outside of that, make sure your radiator fins are clear of any dirt/bugs/debris. Check your fan clutch, should have some drag to it. If it free-spins or is stuck that's a problem.
Lol, make sure there's water in the radiator.
-Have you verified the temp with an IR thermometer?
-What temp thermostat did you install?
-Have you done a thorough flush of the cooling system?
Outside of that, make sure your radiator fins are clear of any dirt/bugs/debris. Check your fan clutch, should have some drag to it. If it free-spins or is stuck that's a problem.
Lol, make sure there's water in the radiator.
#3
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Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
Welcome to the forum!
Second time in as many days I've heard that comment. Water pumps can have their vanes rusted away long before they leak. They don't move much water that way.
The problem could also be due to the fan clutch. There's no way to test them. I suggest you replace both the fan clutch and the water pump. It's not a bad idea to replace your hoses while you are at it. If they are original, they are going to fail soon.
Even if you don't replace them, do inspect them carefully.
At least replace the clamps. I had one break on me going down the road. It was just rusted through, under the hose where it was not easily seen. Instant steam cloud! Had to pull over and have someone bring me some clamps and coolant.
Clogged heater core, most likely. Possibly the blend door is malfunctioning. That's one of the controls inside.
There are a number of threads around here on how to flush your heater core. If it's too badly clogged, it might need to be replaced.
The problem could also be due to the fan clutch. There's no way to test them. I suggest you replace both the fan clutch and the water pump. It's not a bad idea to replace your hoses while you are at it. If they are original, they are going to fail soon.
Even if you don't replace them, do inspect them carefully.
At least replace the clamps. I had one break on me going down the road. It was just rusted through, under the hose where it was not easily seen. Instant steam cloud! Had to pull over and have someone bring me some clamps and coolant.
There are a number of threads around here on how to flush your heater core. If it's too badly clogged, it might need to be replaced.
#4
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Have 91 jeep cherokee. Overheats in parking. Changed thermostat to no avail. Thinking is water pump. But I notice no water leaking from pump. Second radiator turn on when approaching red line, but still advances. If I turn on heater in defrost mode, or any mode no hot air. When i feel radiator top hose feels hot but can easily squeeze it. Any ideas?
Last edited by freegdr; 05-08-2017 at 04:49 AM.
#5
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Year: 1998
Model: Cherokee
Engine: 4.0L
It's a 91, when was the last time the cooling system was overhauled? If you care about keeping this vehicle going I would highly recommend doing a flush and a complete overhaul.