Coolant Overflowing - Toyota Nation Forum : Toyota Car and Truck Forums

cwc418 · 10-25-2007, 11:23 PM

I bought a 1993 Camry XLE V6 (276K) about 3 months ago. The car runs exceptionally well for the miles. Since then I have done quite a bit of preventative maintenance, but there is one thing I cant figure out. The car will overheat periodically. It seems to overflow coolant into the reservior tank. It will only overflow if I have been driving for about 100 miles when it gets really hot. I have replaced both caps, water pump, radiator (it had a small leak), and flushed the system. I have also had a pressure test done and it didnt show any leaks. I also had an exhaust gas test with no evidence of anything in the coolant. When I first bought the car I had a compression test done and it had very good compression. What could cause the coolant to overflow and overheat? Could I still have a bad HG? How hard is it to replace HGs on a V6?

papariccardo · 10-25-2007, 11:32 PM

Sounds like the HG. If you wish to try a patch, consider 'chemiweld' or a local top brand head sealant. Follow the instructions, it seals well enough. I've got a year out of a patched 3VZ after a minor HG leak developed, was still going fine when sold. Never replaced the gaskets on one tho.

digmycelica · 10-25-2007, 11:54 PM

Does this one have a AC cooling fan and a Radiator cooling fan ? Check to make sure the fans are coming on. also change the thermostat.

xtremeskier97 · 10-25-2007, 11:54 PM

Uhh...you didnt replace the thermostat yet?

cwc418 · 10-26-2007, 12:20 AM

No, I have not replaced the thermostat. Could that cause coolant to overflow from the radiator to the reservoir?

Stillrunning · 10-26-2007, 04:57 AM

Quote:

Originally Posted by cwc418

It will only overflow if I have been driving for about 100 miles when it gets really hot.

You've done what you needed to test for HG and I would not suspect that yet. I will assume that there is no sign of water in the oil? Does your heat gauge stay in the normal range? When does it overflow, when you're driving or only when you stop and turn off the engine? Have you had any engine codes? What weight and type of oil are you using? Did you test you oil pressure?

camry93 · 10-26-2007, 06:34 AM

I had a similar problem with my 93 V6. I thought it was the HG but it turned out to be a bad rad cap. You mentioned changing them already but you may have a defective one, for the price of the caps its worth looking into first.
If either one of the caps are not sealing to the proper pressure the system will not pressurize and the coolant will boil and overflow.

ghettosled · 10-26-2007, 07:00 AM

like others said, try replacing your thermostat - its a cheap and easy thing to replace. if its going bad, it might not open or stay open to allow coolant to circulate into the motor, then the hot coolant would build up pressure in the radiator and force itself into the overflow reservoir.

cwc418 · 10-26-2007, 10:15 AM

It overflows only when driving. It will never overflow when at idle. I can sometimes go almost 2 weeks if I dont run it for long distances and just drive it around town. I have caught it overflowing once after I ran it for about 1 hour. I pulled over promptly, opened the hood, opened the cap that goes onto the reservoir and there was a steady stream of coolant coming out of the hose that goes into the reservoir. I have taken the car to two very reputable mechanics they cant figure this thing out. BTW, there is no water in my oil and I have never seen white smoke.

digmycelica · 10-26-2007, 10:38 AM

as said, change thermostat, and check cooling fans.

Stillrunning · 10-26-2007, 12:13 PM

Well you do have 276K on this engine. It's as if there is a bearing or two heating up. For $20 you can get an oil analysis done to make sure there are no excessive bearing materials in the oil. If you want to go this route try Blackstone Labs. They'll send you a free sample container.