I have a 1992 camry that is over heating. I took out the thermostat, changed the water pump. Did a compression test and got 155-160psi on all cylinders. I rented a block tester (the test with the blue color change die that detects hydrocarbons in the cooling system) and got nothing. I also changed the radiator caps. I pulled off the upper radiator hose and flushed the block and radiator both directions and didn't have any back pressure or crap come out. its the 3.0 v6 3vzfe with the hydraulic fan run off the power steering pump. I bypassed the solenoid that tells the fan when to turn on and off so it would be on all the time and it still overheated. I also used a gloved hand to try to slowly stop the fan thinking mabe it had a bad clutch but it didnt slow down at all. I changed the head gaskets about a year and a half ago and didn't know I had to change the head bolts. If the head bolts were my problem wouldn't it NOT pass a compression test? Even with the thermostat out the car drives ok for a while then over heats. when i changed the water pump i took it on the freeway and it got up to regular operating temp for about 30 miles then all of a sudden it starts to over heat. Around town it over heats faster but when it starts to over heat if i shift into low gear and give it high throttle I can watch the temp drop back down to operating temp but once its at idle it will overheat again. Im completely stumped. Any help or ideas would be greatly appreciated!!!

 

Look at my post in response to Camry Runs cold. With a new, tight sealing thermostat it is likely that you have an air pocket behind it. So filling it only tops up one side of the cooling system.

The thermostat prevents the new coolant from completely filling all the water chambers in the block and head. A new thermostat seals off about 1/3 of the cooling system, so you can't fill it to capacity while cold.

The remedy? (be careful doing this) Let the engine heat up to the 'normal' range with the thermostat cap off. You can expect some steam geysers. Start refilling and step back. Refill again and again to until the fluid level stabilizes.

 

but the thermostat is out. i removed it when i first started having the problem and i have two radiator caps. one on the radiator, and the other on the top of the block. if i fill from both spots its filling from both sides of the water pump and unless im mistaken (and i may be im no mechanic) this should keep from having air pockets right??? also i removed the heater core hoses one at a time and flushed the hole system both directions from the heater core lines and didnt have any resistance or garbage come out. yesterday I drove it up and down the road for a while and it over heats at stop lights and once the vehicle is idling. But once i start driving again the temp drops back down. it only over heats while driving once enough of the water boils past the cap that the system is low on coolant.

 

Sorry, I didn't read your question carefully. The original post was sort of long.

I'm no expert, but I don't think engines run well with the thermostat out. Maybe a mechanic here can answer with some certainty. And I didn't know that any Camry's had a second fill cap on the radiator tank. Mine has only the one on the fill block bolted onto the motor.

 

I changed the oil 2 days before all this started. is it possible that mabe a bad oil filter or mabe the wrong oil filter could cause this problem. mabe if the oil pressure is so restricted going through the filter??? Is this posible? I never really thought about it that way before but I have no idea what is causing my overheating problem and Im guessing at **** now???

 

Would be very strange if a bad oil filter caused overheating. The filter has a bypass route for the oil if plugged.

You should be able to put a garden hose into the top of the radiator and have the water come out the bottom without backing up.

The fans are for stop and go driving, etc. If the car is moving at higher speeds there should be enough air flow to cool the engine.

Did you do the block test when the engine was hot?

Any increase in water vapor coming out the tell pipe or the same amount for a longer period of time?

Have you checked the radiator cap?

 

The only things left would be engine timing and radiator. Instead of buying a new one, first take it out and have a radiator shop flush it and check the flow.