199 ford ranger overheating

[geohauss]

I have a 1999 Ranger that is overheating during the idle. If I rev the engine, it will cool down. A bit of background: Back in January the fitting that the heat sensor plugs into (which screws into the coolant housing) rusted out. This got rust in my coolant system, and I had it flushed for the second time on Thursday (26APR07), and it is still heating up during idle.

Does anyone have a clue as to what might be causing this? What can I do?

I appreciate any help. Thanks.

[98XLTKid]

i don't know if this is the problem but have you tried replacing the thermostate?

[manlystanley]

Originally Posted by geohauss

I have a 1999 Ranger that is overheating during the idle. If I rev the engine, it will cool down. A bit of background: Back in January the fitting that the heat sensor plugs into (which screws into the coolant housing) rusted out. This got rust in my coolant system, and I had it flushed for the second time on Thursday (26APR07), and it is still heating up during idle.

Does anyone have a clue as to what might be causing this? What can I do?

I appreciate any help. Thanks.

Check your upper radiator hose to see if its hard or not. If not, it's probably your thermostat or water pump.

Best Regards,
Stan

[Fredoe37]

Im not sure if that model is still using the fan clutch system or not...if it is try spinning the fan when the engine is off and heated up...if it spins freely then you most likely have a bad fan clutch.

[DonSor]

I assume that the temperature gauge is giving the right indication. You stated that the engine gets too hot while idling but cools down when you rev the engine up. How does it do when driving the vehicle? I also have a 99 4.0L Ranger. The fan clutch has a "viscuous pump" and a spring-like temperature sensor. When you first start the vehicle (hot or cold engine) the fan runs at the same speed as the pump. The viscuous fluid in the clutch builds up and disengages the clutch and the fan slows down. From then on the fan clutch responds to the temperature sensed by the spring. The stat is easy to check. I'm suspecting it's the fan clutch. if you do decide to replace it check the pump thoroughly because sometimes a bad pump could cause the clutch to go bad and vice versa.