'94 Es Overheating!

[82DMC12]

Hey Group,

My 94 ES300 has been overheating the last two days. It has almost 120K on it. The temp gauge is always right below center but yesterday I was just driving around town and saw my check engine light come on and my temp gauge was pegged!! I shut the engine off and coasted into a gas station parking lot and found my coolant was boiling/bubbling with steam in the overflow. Since my work is just two blocks from there, I let it cool down (but still too hot to open rad cap) and then drove to work and shut it off for the rest of the day. Drove it six blocks home after work and popped the hood, added one gallon of toyota red coolant. It was fine until today when I took it to the lakes (about an hour away) and it was running hot most of the way there but not overheating. On the way home it got so hot I had to stop in nearly every town to add coolant or water, whatever I could find.

Now my car is in my garage with an engine full of mostly water or yellow universal coolant. I have never had cooling system troubles until now. There is no coolant in my oil that I can tell. Each time I added coolant I ran the engine and squeezed hoses and ran it up to 1500 RPM while adding coolant to try and bleed it. I see no leaks except for where coolant has been overflowing from the reservoir all over the passenger side where the ABS system is.

Any ideas on what the problem is? I wonder if my thermostat is all crudded up and is sticking, causing the coolant to boil out.

I plan on changing the thermostat and reflushing with toyota red coolant. Any other suggestions?

I think the water pump was changed about three years ago and the rad cap was replaced as preventative maint about a year ago at my last flush.

Andy

[Lexusfreak]

No leaks whatsoever? I agree to do a full engine coolant flush (with distilled water), thermostat & rad cap replacement.......I would have the water pump inspected & would even consider using Red Line water wetter (half bottle) into the recovery tank after the flush. What condition are the actual rad & hoses in?

[Toysrme]

& make sure the hydraulic fan is working. With the engine on, short OP1 & E1 in the diagnostics port to see if the fast turns fast.

[82DMC12]

No leaks whatsoever? I agree to do a full engine coolant flush (with distilled water), thermostat & rad cap replacement.......I would have the water pump inspected & would even consider using Red Line water wetter (half bottle) into the recovery tank after the flush. What condition are the actual rad & hoses in?

I know the hydraulic fan is working because it was running while I was adding coolant at the gas station. The hoses feel a little soft on one side but they aren't expanding or cracked. The radiator is rust-free (but its aluminum, right?). The grill is not full of crud or bugs. I really don't see any damage or time-related problems to any of the cooling system components. Luckily today the car is running fine, starts up OK, has plenty of power, and no foam in the oil so it looks like I didn't cook the engine.

The thermostat must be on the driver's side of the engine. Any tips on replacing it? Should I get it from Lexus or is one from autozone OK? Is there a gasket or sealant needed?

Andy

[Toysrme]

Yes, the thermostat on the 1mz-fe is on the driver's side.

Check that 94 Camry repair manual for instructions & such on it.