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2010 JKU Overheating Issue

2963 Views 2 Replies 2 Participants Last post by  cptslewis
Having a high temperature issue on my 3.8. 42K miles on the odometer. The temperature is now getting past half way. Between 5/8 & 3/4. No overheat light yet. When at operating temperature and I turn it on it will jump to 3/4 before the fan kicks in on high to knock it down to 5/8. On highway above 55 w no load(level or going downhill). It stays at 5/8. Top radiator hose is pressurized. Thermostat is less than a year old. Fan is operating at low and high. Radiator fins are clear. I do have a rugged ridge bumper w Q9500i recessed winch.

I am leaning towards a weak water pump even though their is no chirp or weeping. However I will flush coolant system before I pay for pump. Coolant is original and never been changed. No gunk at bottom of reservoir but who knows.

Does the radiator have a drain cock? Did not notice one.

Any other feedback would be appreciated.
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Sounds like its time for a coolant service first. Flush and start from there. Why have you replaced your thermostat already? Sometimes a tstat can go bad. I would replace and flush first.
The only reason I replaced the thermostat was because the water outlet was leaking. So I did it at the same time. Doing the flush now and going to do the thermostat but had another question. I heard and saw my fan kicking in and felt it pulling the air through the radiator well.

However should it have a low mode as well? It's only going full bore once it reaches midway. Doesn't turn on at a lower setting.
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