Camry '97 Overheating

[Martin_W]

Hi Everyone,

I have a Toyota Camry '97 Vienta with 3VZ-FE. It has a tendancy to get hot to the verge of overheating while covering long distances. It doesn't loose water nor does it vent through the overflow nor foul the oil so I *think* the head gasket is fine. This condition only presents itself during hot weather (30*C+) and after cruising at 2KRpm+ for around 50Km. I modified the thermostat by cutting off the valve but it still gets hot.

I was able to establish fliud flow whilst starting the engine with the radiator cap removed (with modified thermostat) and was able to observe movement but have no idea how much to expect.

The fan runs fast and loud when getting hot (this is the hydraulically driven variant from the Power Steering pump)

Prior to modification, I tested the thermostat and it opened at 80*C (as expected).

I measured some temperatures around the engine.

Water hose entering the top of the radiator was around 100*C-110*C, whilst water hose exiting the radiator and thermostat housing were at around 90*C. Should I expect more than a 10-20*C termperature differential through the radiator?

Any ideas?

Thanks in advance

Martin

[Old Red Celica]

Is the Radiator and pipework all clean and flushed out?

Have you actually checked the water level in the cooling system, ignore the level in the overflow bottle.

[Martin_W]

Is the Radiator and pipework all clean and flushed out?

Have you actually checked the water level in the cooling system, ignore the level in the overflow bottle.

Thanks for the response,

I fill the cooling system through the radiator cap and not the overflow bottle. The system is not loosing water. I reverse flushed the entire block (with the thermostat removed) using my garden hose but I haven't had the radiator pressure tested. There was no debris or fluid discoloration (as in rust).

Thanks again,

Martin

[Old Red Celica]

As long as the needle keeps out of the red there should be no problem, without sounding like I'm trying to teach you to suck eggs. Are you running plain water or an antifreeze/Toyota Coolant mix?

As I'm not to sure on whether you suffer from freezing conditions over there.

The fact it seems to be running cleanly (without crud in the system) is a good thing as abviously the more crud in there the less chance it has of keeping everything cool.

[Martin_W]

As long as the needle keeps out of the red there should be no problem, without sounding like I'm trying to teach you to suck eggs. Are you running plain water or an antifreeze/Toyota Coolant mix?

As I'm not to sure on whether you suffer from freezing conditions over there.

The fact it seems to be running cleanly (without crud in the system) is a good thing as abviously the more crud in there the less chance it has of keeping everything cool.

Thanks for that,

Freezing isn't an issue, but hot summers is. I have always run anti-freeze/boil. I know from discussions with Mechanics, that the 3VZ-FE engine suffered from some over-heating issues, but not like this. I had a falcon many years ago and it's head gasket went and it was quite obvious as it wouldn;t idle smoothly and the oil had turned into custard. I've been informed that when the 3VF-FE blows, 99/100 times it will blow out into the water jacket. There are no bubbles rising in the filler cap (not the overflow canister) nor is it loosing water. The needle rises only when the engine is under load.

Once the needle has risen a bit, I can set it in neutral and rev the engine at 3K RPM for around 2 minutes and the temperature returns to normal.

I've flushed the radiator with a caustic solvent and copious amounts of water with no joy, and I've made sure that the cooling fins are not blocked.

Everything seems to point to the radiator but I can't be certain until I can get a Block Test done for gasket venting.

In any case it looks like I might have to remove the radiator to get it pressure tested.

Thanks

Martin