96 3.8 V6 with 140,000 miles

I am trying to diagnose if I have a blown head gasket. Current symptom is the engine will randomly overheat. After it over heats the radiator starts leaking from the side(opposite end from the filler cap). After replacing the radiator(used from a junk yard) and refilled the water level, the car ran at normal temp for 1 hour. Started it up the next day drove it to work, just fine, but then on the way home the temp rises and once again the radiator starts leaking(same place as it did on the first radiator). Also at the time the car was overheating I turned the heater on and it was blowing hot air.(referencing there was water in the cooling system)

No smoke from the tailpipe, no water in oil, and no oil in the radiator either. The car runs perfectly fine.

I replaced the radiator, water pump(new) and thermostat(new). Note: When refilling the cooling system after replacing these components, I bleed the system on an incline including bleeding using the screw at the thermostat.

My next thought is to try a combustion leak test kit(kind that connect on the Radiator) and changes fluid color.

What are the odds it is a head gasket?

Thanks,

 

ive read that the 3800 has more problems with the intake gaskets than the heads

ive seen this vid its good
http://www.youtube.com/watch?v=QA7KVQq9vKA

 

If your to the point you are overheating due to the headgasket you will fail and basic pressure test. Is your fan running? You can borrow a tool from autozone with a deposit.


http://www.youtube.com/watch?v=DgxbPHX-W_M

 

You bleed the system with the engine warm enough for the thermo to be open? Just checking?

 

Thanks for bringing this up. After ensuring I completely bleed the cooling system while the engine was warm and replacing the Radiator cap, the car has not overheated yet.

I am going on 4 days now with no more temp issues, so I am keeping my fingers crossed.


Thanks for your suggestions.

 

Make sure you don't have any "mud" in your cooling system. "Mud" forms from neglected Dex-cool that's left in too long OR mixed with conventional anti-freeze, both which are likely. "Mud" will kill your cooling system performance.

Also make sure you have the plastic air deflector under your front bumper that funnels air through the radiator and a/c condenser. The car will really struggle to stay cool without it.