93 Grand Voyager w 3.3 overheating

I keep having an overheating problem with this van. It's blown out a hose (replaced), the fan seems to come on, I've removed the thermostat, plenty of coolant, no leaks, etc. Any ideas? Thanks.

Reply to
patrick
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Is the thermostat in the right way? Are there any (improperly installed) collapsed hoses? Could you have trapped air that was not purged (use the bleeder at the thermostat housing)? Or, if you blew the hose and lost all the coolant you could have also blown a head gasket. BTW, how old is the radiator cap? It's cheap to replace and if more than a couple years old it might be a quick fix. Last possibility would be a clogged radiator given the age. Good luck.

Good luck.

Bob

Reply to
Bob Shuman

How often have you flushed the cooling system and changed the antifreeze? How many miles on the van? I'd guess a clogged radiator core, but without more details that is only a guess.

Does it overheat while cruising at speeds above 40 or so, or only in town or at idle?

Matt

Reply to
Matthew S. Whiting

Thanks for the help. Yesterday I removed the thermostat completely, it overheated about four hours later. It seems to overheat when we're driving, not at idle. BTW what is the easiest way to check for a clogged radiator on this car?

Thanks aga> > I keep having an overheating problem with this van. It's blown out a hose

Reply to
patrick

If it is overheating at highway speeds with the thermostat out then that pretty much rules out the electric cooling fans and, obviously, the thermostat. Pretty much leaves a clogged radiator (most likely depending on mileage and maintenance history - neither of which you've yet mentioned), water pump impellor failure (highly unlikely), or head gasket failure that is allowing combustion gases into the coolant.

I've never had the hoses off either of my minivans so I'm not sure if you can see the ends of the tubes through the radiator cap or hose outlets. Visual inspection is normally the easiest way to see clogged tubes.

Matt

Reply to
Matthew S. Whiting

Do not rule out the Head Gasket. While it is not a common problem on the 3.3, it does happen.

I had to do the head gasket on my 94 GC 3.3. I was luckier though, the leak was visible from the outside of the engine. Based on feedback here, even though I was skeptical, I had the head gasket done. No quesiton, that was the problem.

I have not lost a single drop of coolant since the head gasket was done. And no overheating either! :)

Good luck

Reply to
Cloaked

Thanks again for your advise. The car (it's a taxicab) has over 300k miles and has been well maintained. I've inspected and/or replaced all of the hoses, reversed the heater core flow and flushed the entire system. I get very good water flow from every connection on the system. If it's the head gasket, won't my oil turn white?

Thank you , Patrick

Reply to
patrick

You won't necessarily have your oil turn white. Remember that the oil pressure can be 40 to 80 psi while the cooling system is 16 psi. I had a head gasket go on my 1991 3.3 5 years ago. Haven't had a bit of a problem since. If you've got a shop that has an exhaust sniffer you can have them hold the sniffer over the filler neck & check for hydrocarbons. Their prescence would indicate exhaust gasses in the coolant. Check the radiator while the van is running & see if there are any bubbles in the coolant. They might also be an indicator of a leaking head gasket.

Good Luck & God Bless,

Tom Heintz "Mopar Maniac"

Reply to
Tom & Debbie Heintz

I have never had the head off of a 3.3L so I can't say for sure, but most engines have both water passages and oil passages running near the cylinders. A head gasket failure can cause combustion gases to enter the oil, the water, or both. Also coolant and oil can comingle. Do you lose any coolant over time? Any oil? Most head gasket failures I've seen go both ways - combustion gases into the coolant, but also coolant sucked into the cylinder (intake stroke tends to cause lower pressure in the cylinder than in the coolant). If you aren't losing coolant over time, other than what is lost if you are getting to the boilover point, I'd question if it was a head gasket leak. Another possiblity, especially with the miles you have on the van, is a cracked head. I haven't heard of this being a problem area for the 3.3 engine, but then I'm not sure many have 300K+ miles on them.

Might be time to suck it up and turn the problem over to a competent garage or dealer.

Matt

Reply to
Matthew S. Whiting

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