96 Town & Country overheating

I have been working this issue for a while and tried everything I can think of.

The radiator eventually boils out all the water from the radiator causing the engine to not cool properly. Once I fill it back up it runs fine. It takes many weeks and possibly months for this to happen and I give up daily checking for a while and then before I know it the water is low and it's hot.

I have changed the thermostat. I had a diagnostic code that said the fan relay was bad, so I replaced that. I flushed the system. I replaced the draincock (because I broke it doing the flush) and that is tight and leak free as ever. The system doesn't lose water at rest when parked. No fluid lost while stopped. It has to be lost when it is running and on the road.

One thing I am wondering about is the A/C. It is cooler now in California so the A/C is mostly off (though the wife loves to have it on once it hits 70 degrees outside.) The last few days warmed up to above

80 and I know the A/C was turned on. Is there a place that could lose water in the A/C?
Reply to
Just Me (remove
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Since you say that it does not overheat at idle, it is probably safe to assume that the fans are coming on correctly. Also, since it is a Town and Country, it probably does not have the 2.4L which has a known problem with headgasket failure.

Have you done a flow check on the radiator and checked the belt to ensure that it is not slipping? It looks like you have checked all the usually stuff.

-Kirk Matheson

Reply to
kmatheson

One thing that often gets overlooked is the radiator cap. It is supposed to hold a certain minimumum pressure before venting. As radiator caps age, they sometimes will hold pressure, but not the FULL rated pressure. What happens then is that water in the engine boils very slowly and the vapor is slowly released through the radiator cap. Eventually, enough is lost that the level drops significantly. That's the first thing I'd check. Heck, I wouldn't even CHECK it, I'd just replace the darned thing and see if the problem goes away.

Do you mean coolant water getting into the AC system? No way, absolutely impossible- they're two COMPLETELY separate systems. Now, running the AC does put a heavier load on the cooling system because the radiator only gets cooled by air that has already been pre-warmed by the AC condensor. If you have a cooling system leak (like the radiator cap I described above) its entirely possible that running the A/C will cause coolant to disappear a little faster.

Reply to
Steve

Slow, slow leak.

Have you had the cooling system pressure-tested? Try putting it up to

16psi when cold, and look for drips.
Reply to
Joe Pfeiffer

Sounds like you have a slow leak in your cooling system. It might be hard to find because if it is a really slow leak, most of the coolant will evaporate before you see a drip. I would check all the hoses ends to see if there are any signs of a leak.

----------------- Alex

Reply to
Alex Rodriguez

Your two most likely problems are either a bad head gasket or a leaky water pump. On the 3.0 engine sometimes the water will pool on the engine and boil off and you'll never know it until it's all gone.

Reply to
Robbie and Laura Reynolds

Hi...

A really old guys olden days trick, if I may?

Grab one of the ready to be thrown out white towels from your house. Cut it into strips, perhaps three inches wide. Slit both ends of each of the strips for a few inches.

Wrap one around each of the possible suspect hose ends, and the rad cap. Tie it with the slit ends.

Then drive around for a while. If any of the connections is bad it will be wet and a little stained. And perhaps HOT, so be careful :)

Take care.

Ken

Reply to
Ken Weitzel

Have you checked the hoses and such for the rear heater?

Reply to
Steve

Replace the radiator cap. It may no longer be holding pressure and you lose fluid out the overflow drain tube. make sure fans run properly and the radiator is not plugged. Short of that, it could be a head gasket, but check the other stuff first.

Bob

Reply to
Bob Shuman

I found a small leak in the radiator itself by letting it idle hot for a while. I assume that is where I am losing pressure and how it is leaking while driving. It stops leaking when cool and it is very slow when hot and doesn't ever deposit on the ground.

I am trying some radiator stop leak for now, but it seems not to be working in the brief time it has been in.

Where is the best place to get a new radiator? Autozone has a standard two row for $179 and a HD 1 row for $209.

Should I get a better one? I only do standard, local driving.

Just Me (remove to reply) wrote:

Reply to
Just Me (remove

Don't use stop leak as it just plugs up the radiator.

HD radiator usually is three rows (regular is two) not one. IIRC, most Autozone low end radiators are made in China.

Bob

Reply to
Bob Shuman

Update:

Sorry, I used stop leak. I only care to make the van run for another two years before replacing it so I hope it doesn't screw it up too much. Not worried that it will screw up the radiator especially since I'll replace it if that is still the issue.

After a day of light stop-n-go driving, the leak has stopped. I was surprised. A brown powdery substance remains where the leak was, but when running and under pressure there is no more water flowing out. The car runs great as it has before, but we'll see how long before it boils out.

Still would like advise on where to buy a radiator if this fix doesn't work for the long haul.

Just Me (remove to reply) wrote:

Reply to
Just Me (remove

Buy from the radiator shop that supplies the other radiator shops.

Reply to
Robbie and Laura Reynolds

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