99 xj keeps overheating
06-21-2016, 09:52 PM
#1
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Model: Cherokee
99 xj keeps overheating
I have a 99 xj with lots of different mods.
It keeps over heating and here is the list I have done so far to fix this problem.
New water pump
New thermo
Clean radiator really well and pressure tested it.
Coolant flush and put new coolant in and got all the air out of the system as far as we can tell.
Also it has 3 aux. fans on the radiator 2 turn on with ignition and 1 on switch but always keep it on.
It will over heat after about 20 min running. Not sure what to do since it seems like we have done everything. Any help would be great.
It keeps over heating and here is the list I have done so far to fix this problem.
New water pump
New thermo
Clean radiator really well and pressure tested it.
Coolant flush and put new coolant in and got all the air out of the system as far as we can tell.
Also it has 3 aux. fans on the radiator 2 turn on with ignition and 1 on switch but always keep it on.
It will over heat after about 20 min running. Not sure what to do since it seems like we have done everything. Any help would be great.
06-21-2016, 10:22 PM
#2
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Year: 1999
Model: Cherokee
Engine: 4.0
I have a 99 xj with lots of different mods.
It keeps over heating and here is the list I have done so far to fix this problem.
New water pump
New thermo
Clean radiator really well and pressure tested it.
Coolant flush and put new coolant in and got all the air out of the system as far as we can tell.
Also it has 3 aux. fans on the radiator 2 turn on with ignition and 1 on switch but always keep it on.
It will over heat after about 20 min running. Not sure what to do since it seems like we have done everything. Any help would be great.
It keeps over heating and here is the list I have done so far to fix this problem.
New water pump
New thermo
Clean radiator really well and pressure tested it.
Coolant flush and put new coolant in and got all the air out of the system as far as we can tell.
Also it has 3 aux. fans on the radiator 2 turn on with ignition and 1 on switch but always keep it on.
It will over heat after about 20 min running. Not sure what to do since it seems like we have done everything. Any help would be great.
06-21-2016, 10:39 PM
#4
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Year: 1998
Model: Cherokee (XJ)
Engine: 4.0L
3 fans? 2 on one side 1 on the other? if the one on the other is trying to pull air instead of push it that could be the problem/ What kind of fans are they?
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06-22-2016, 12:08 PM
#8
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Just 3 fans that cover the whole radiator. And all pull the air. If I remember right they are just 8" electrical fans
06-22-2016, 12:32 PM
#10
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Year: 1993
Model: Cherokee
Engine: 4.0
How many cfms do those fans pull? An 8 inch fan without a shroud isn't going to pull much air through the radiator, even with three you probably don't have anywhere near enough airflow, maybe three 11 inch fans with shrouds, or the stock fan setup.
06-22-2016, 12:37 PM
#11
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Year: 1998
Model: Cherokee
Engine: 4.0
When is it overheating? A while ago I had an overheating issue and everything tested fine, however when it was under load it would over heat. Turned out my radiator was partially clogged, so it was letting coolant through but not enough to properly cool the engine. It would idle fine though. What state is your coolant in?
06-22-2016, 01:03 PM
#12
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They are 3 10" fans. It is meant to replace the stock set up but the shroud was broken so I took it off and it worked for a little while then the water pump gasket blew out and I replaced it and the the thermo and someone like up top. But I just didn't think the fans would need it
06-22-2016, 01:04 PM
#13
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When is it overheating? A while ago I had an overheating issue and everything tested fine, however when it was under load it would over heat. Turned out my radiator was partially clogged, so it was letting coolant through but not enough to properly cool the engine. It would idle fine though. What state is your coolant in?
06-22-2016, 01:16 PM
#14
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Year: 1997
Model: Cherokee
Engine: 4.0
You have to have a shroud to force air to be pulled through the radiator. Without a shroud you pull air from around the radiator reducing cooling.
