Just changed the harmonic balancer, radiator and thermostat, but car starts running hot. Please help.
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1999 Lexus GS300 Question: '93 Lexus GS300 is running hot.
Answer #1Rojo1 August 31, 2013, 19:35Technician
THERE MAY BE A BLEEDER VALVE THAT NEEDS TO BE OPEN IN ORDER TO PURGE AIR FROM THE SYSTEM WHILE FILLING.
Replylexuser, September 20, 2013, 15:32Rookie
Thank you, will have it checked. The mechanic told me that there is a lot of pressure in the motor that causes the water to backup in the reserve box. He suggests that it could be a blown head gasket, which I find hard to believe since the car never ran hot until the harmonic balancer was changed.
Answer #2goodguy September 20, 2013, 10:33Master
check to see if your cooling fans are working
Replylexuser, September 20, 2013, 15:35Rookie
The main radiator fan is working, but not the cooling fan. Don't know how to get it to work. Please advise.
ReplyRojo1, September 24, 2013, 04:36Technician
The only way I can see a connection between an overheating condition and replacement of the balancer on a GS300 is through the water pump drive belt. I believe the water pump has a separate belt with its own adjustment point and all belts must be loosened in order to replace a balancer. I'm betting the water pump belt is too loose to turn the pump fast enough at higher speeds or possibly any speed. Incidentally, temperature and pressure are directly proportional so as the engine heats up, the pressure will also rise. To address your concern with the cooling fan: at only two times will both fans run simultaneously. One is during overheat and the other is when the A/C is running. Check your belt..