overheating after replacing the radiator and thermostat

2004 JEEP GRAND CHEROKEE
90,000 MILES • 6 CYL • 2WD • AUTOMATIC
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BUTCHRENO
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After replacing the radiator and thermostat, I let the car idle
for 20 minutes temperature went to about 220 electric fan came on for only
about one minute and shut off. From this point temperature continue
to climb until warning light came on. Fan never did come back on??
Sep 4, 2020 at 7:38 AM
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ASEMASTER6371
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Good morning,

How did you bleed the system of air?

What I do is leave the cap off, have someone inside revving the engine until 1,200 RPM's and you under the hood and add coolant as needed. When the thermostat opens, it will burp the air and you add the coolant. Have the person inside the truck turn on the heater. When they have good heat, there is no more air.

Try this. It may be just air in the system from the repair.

Roy
Sep 4, 2020 at 7:46 AM
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BUTCHRENO
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I did as you recommended but no luck. Is it possible to have a bad fan control and it come on for such a short period of time? Should the fan stay on until the temperature goes down to normal??
Sep 4, 2020 at 11:21 AM
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ASEMASTER6371
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Did you have this issue prior to the repairs?

https://www.2carpros.com/articles/how-an-electric-cooling-fan-works

Why did you perform these repairs?

https://www.2carpros.com/articles/engine-overheating-or-running-hot

I am concerned for a possible head gasket issue if it overheated.

https://www.2carpros.com/articles/head-gasket-blown-test

Roy

Sep 4, 2020 at 11:48 AM
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BUTCHRENO
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The radiator was cracked. So I replaced it after about a week car overheated again so I replaced thermostat. I don’t understand why the elect fan shut down after only running a few minutes when the car continued to over heat.
I don’t think head gasket it was shut down immediately.
Sep 6, 2020 at 12:01 PM
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ASEMASTER6371
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If there is air in the system from a leaking head gasket, the fan will not work long as it needs to be in coolant to send the proper signal to the relay for turning on the fan.

I attached the wire diagram for you to view. Check the fuses for power with the key on to be sure power is sent to the relays.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-check-a-car-fuse

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Roy
Sep 7, 2020 at 4:54 AM