couple of questions about overheating V6, '93 Camry

[DCM]

I'm not a Camry owner, but I got a call from a mechanic friend who's working on one. It's heating up, but not under any specific load, rpm or vehicle speed. The temp gauge fluctuates mildly while driving, then out of the blue it'll shoot up to just under the red. Coasting down hill does pretty much nothing to lower it (it's an automatic, if that makes any difference).

Aside from the probable head gasket failure, are there any known problems with the hydraulic fan? It's speed varies but it certainly doesn't spin very fast or "lock up" like a clutch fan.

Thanks for any input.

[eyeball96]

Check the Radiator top for cracks, Thermostat, or Radiator cap! Could either or, all three.

I'd replace the Rad cap first, if the Radiator checks out OK!

[Day Tripper]

Check your power steering fluid level. I have the same car and a leaking ps was causing over heating when the fluid was low.

[whip_cracker]

Check the thermostat on the left side of the engine block there... prob needs replacing anyway. Pain in the arse to replace, gotta take the washer bottle out etc. Filler rad cap and cap on the tank itself should check to see if the rubber is gone or the pressure release valves are still good... replace them both with 1.0 pressure cap on the tank and 1.1 pressure cap on the filler neck. I'd probably just replace the caps with something that can hold higher pressure (maybe 1.5 instead).

It's quite possible for the solenoid to go, but I'm yet to come across any mechanic or any radiator specialist have an issue with the 3VZ radiators and hydraulic fans... which I guess is good

Good luck mate.

[DCM]

Thanks for the replies.

It's had the rad replaced recently, and was apparently overheated a couple of times. Thermostat is new, and p/s fluid is full. I guess that leaves the gaskets!

[eyeball96]

?Did you replace the Rad Cap

[DCM]

Yes, sorry I forgot to mention that.

[csaxon]

75% of the time after work is done & you're overheating, it's because someone didn't plug the connector in on the powersteering pump. The other 25% of the time the thermostat is installed incorrectly, or is faulty. Usually, if a P/S fan doesn't spin fast, it's because the connector has simply been unplugged
.
The radiator fan is powered by the power steering pump. You loose fluid, you loose the fan. . It's a fluid motor, it slips like crazy - don't worry about it.
The fan has 2 speeds low and high.
If you'll look on top of the power steering pump there is an extra outlet / inlet with an electrical plug by them.
The electrical plug is a solenoid controlled by the cooling fan ECU. The ECU opens the solenoid all the way & the fan spins fast..
The only problem is if the electrical connector that plugs into the top of the power steering pump is not connected. Which is common when people are changing the P/S belt.




You can check that the fan/fan computer/high-pressure relay are working correctly by opening the Diagnostic port in the engine bay & bridging E1 & OP1. Use paper clip or jumper test wire. This should give more fluid to the fan, causing it to spin faster.
In the Diagnostic port, bridge E1 & OP1 & the fan will spin at high speed.

[dadsrepairshop]

I have a similar issue with my daughter's 92. I tried jumpering E1 to OP1 while the car was running and nothing happened to the fan speed. Is this a symptom of the power steering electrical connection not being connected?
The fan on this car actually slows down as the motor heats up and idles down. The coolant temp at the thermostat (mechanical gauge) goes past boil 212F/100C and the fan keeps friggin idling along. I have replaced the fan control sensor next to the thermostat, the coolant temp sensor in the heater bypass piping, radiator previously when top split off it and the thermostat (jiggle port up with 2 extra holes drilled into it to improve preopening circulation. Still will not stay cool on hot day in traffic or slow cruisin.

I tried disconnecting the sensor next to the thermostat with the car running and it did not kick the fan into high gear like I believe it should. I am getting more frustrated by the nite.
I have yet to check the ECU under the glove box but that will be tomorrow nite.
Have burped the system to remove all the air or believe I have. System does not take any excess fluid once shut off to cool and does not bubble on startup right up until it starts to boil out the top.

Any and all suggestions are welcomed.
Thanks for listening
Dadsrepairshop

[davemac2]

dadsrepairshop,

as others have said, it's fairly rare for the hydraulic fan motor to fail. I think the only thing that should affect the fan is the fan temp sensor on the rad inlet pipe, the fan ECU, and that solenoid near the PS pump. If you remove the solenoid connector and try to fire it directly and the fan does not go to full speed, it's either that solenoid or the PS pump itself. The only other thing would be maybe the fan itself is not firmly connected to the motor.

davemc

[dadsrepairshop]

thanks davemac2
I am just heading out to locate the PS solenoid and make sure that connection is good.
Then its into the harness at the fan computer.
The PS pump appears to be moving a lot of fluid when the car is running. There is a steady JET coming into the reservoir and it is not foamy.
So here's hoping for the PS solenoid connection but time will tell.
Thanks again.
Dad

[whip_cracker]

This looks like some useful info... awesome.

So, considering it's "winter" here... I shouldn't be expecting to see my radiator going flat out all the time like I would in Summer?

Are these pics taken off a 3VZ? I had a looksie in the engine bay a sec ago and couldn't exactly find that part... where should I be looking? Towards the front near the radiator? Left or right side? What a pain in the bum ay..

Cheers

[dadsrepairshop]

whip_cracker
on my 92 3.0L it is located at the back of the engine vertically below the timing belt cover. Actually easier to see from underneath the car. Put it on ramps, put your head up between passenger tire and frame just rearward of the suspension and it is a white connector standing all by itself..sorta. In between the piping coming out of the power steering pump.
Many thanks to csaxon for the pics. Made it easy to find.
Dad

[whip_cracker]

Thanks mate, I'll check it myself when I get the CVs replaced tomorrow... only because I don't have any Jackstands. Should be interesting to see how it goes.