Mtjeepgrndcherokee

I have a 2002 Grand Cherokee Laredo, 4.7 and it overheated. I converted the hydraulic fan to electric off of 2000. Fan works fine. Power steering pump is going out though. It has a new radiator, water pump, tstat. I don't know why it is still overheating, unless I have a cracked head. It has about 140k on it. No leaks, white smoke or signs on spark plugs of coolant in combustion chamber but still losing coolant. I am stumped!!!

tthenrie

"...New radiator and water pump..." Questions: Did you use the correct coolant? Should be the orange stuff. Did you properly bleed the coolant system? If you left bubbles in the system, that would explain the overheating and having to add coolant. Also, I have had poor luck with the thermostats currently supplied by the regular parts houses. I highly recommend a Mopar thermostat. If the answer to the second question is "no", then try opening the plugged port on the engine side where the radiator hose connects to the top of the engine on the driver's side. Let the vehicle run until there are no more bubbles coming out. The engine must be at running temperature, so that the thermostat is open and coolant circulating.

Also, a question as to why you removed the hydraulic fan and went with electric. The hydraulic fan is a pretty good and reliable system, as long as your power steering pump is in good shape (apparently yours is not) and you are using the correct PS fluid. I'm wondering if your electric fan is not operating correctly, turning the correct rpms to cool the engine at varying engine temps. I don't know anything about the conversion, but I expect there are sensors that also must be changed out to ensure proper function.

Mtjeepgrndcherokee

Yes, new radiator and water pump. Yes, bled the system when I filled it. I took out hydraulic fan because it took a dump and they are really expensive to replace. I used the 2000 Jeep Grand Cherokee conversion so it works good. I know it was bad because the power steering pump was just replaced not long ago. I tried running without Thermostat and it didn't matter. I am now taking it in to get the heads and head gaskets checked/fixed or replaced. I did check for water in oil, but no oil, checked for oil in water or bubbles, no on those either and pressurized the system, no leaks. I have no other option at this point.

tthenrie

Just make sure the shop that does the work puts the correct coolant in it when they close up the motor. The green stuff is not compatible with the aluminum heads and radiator.