Steam Being Pushed in Antifreeze Reservior

You may have a blockage, an air lock or a leaking headgasket.

Sounds like a leaking headgasket to me. Is there oil in your coolant, or visa-versa?

Why not try another pressure cap just for kicks?

Let's make sure you understand how this system works, first... If you are low on coolant, from: - a leak, -blown head gasket, - cracked head or - gasket, etc,

the water in the block will vaporize and blow out steam via the two way valve in the radiator cap. ¨

A stuck thermostat or an inoperative fan can also lead to overheating, as can a blocked radiator. A bad radiator cap will not hold pressure and may allow steamover too.

The steam may even blow the coolant reserve out of the reservoir.

IF you have coolant in the reservoir when this is over, and IF there is not a big leak in the system, the vacuum which develops in the system WHEN IT COOLS, WILL suck coolant back into the radiator.

So, you need to start with a cooling system full of coolant (no air pockets), a new radiator cap and thermostat, and coolant in the reservoir. Look carefully for leaks in the system

Then, as you drive it, watch it carefully. Don't let these little engines overheat. If you didn't have a serious problem before, you MAY have if you overheat them.

That is a great post. Thank you very much. I am loosing water from I think the radiator.

I should replace it, then the cap, bleed the air out, then check it again. If the thermostat is readily accessible while doing this, now is probably a good time to do this too, right?

Replace it now while everything else is apart.

You might be able to get the radiator cleaned and repaired at a radiator shop for a lot cheaper than replacing it. Depends.

But, yes, replace the thermostat while you are at it. And if the hoses are getting old, replace them too. Hoses will often last for several years, but are fairly cheap (if you don't buy at the dealership). If you have never replaced them on this 93, best do it now.

The cap will take five minutes to replace, and cost five dollars. Therefore you should do it first if you're going to be just swapping out parts without testing anything.

The radiator will cost considerably more, and I would be reluctant to replace it without first doing a leakdown test to verify that it is really bad.

The same tool used for the leakdown test will also allow you to test a cap for leakage.

The thermostat isn't causing your problem, but if you're pulling the radiator you ought to replace it anyway, because sooner or later it will cause a problem and it's easy to do when the thing is all apart anyway.

--scott

I would recomend you DO NOT try and get a radiator cleaned. A reputable radiator shop will tell you up front that it is a waste of money. I have NEVER seen a radiator cleaned successfully. Buy a new one, they can be purchased very cheaply if you shop around.

All good avice but you are confusing a " leakdown test " with a " cooling system pressure test ". A leakdown test is used check for the cause of low compression inside a cylinder.

A cooling system pressure tester is used to check for cooling system leaks and, as you stated, can also be used to check radiator cap for proper operation.

My experience has not been the same as yours. A good radiator shop can clean and repair many types of radiators. They can recore ones where the tubes are irrecoverable, or even make custom radiators. And, they can provide new radiators.

I don't know what you are calling a radiator shop, but I respectfully suspect that you have never done business with a competent and professional one.

To recore a radiator is not the same thing as attempting to clean it. Mike is correct that cleaning is a waste of time.

Why so? I've seen them boiled out, rodded out, successfully lots of times.

Usually they leak when they're in such poor condition and you attempt to clean them.

When I take them into the radiator shop, and if they are brass radiators, they boil or rod them out, pressure test them, repair any leaks (or recore if necessary), repaint them, and they are as good as new.

Now I realize that plastic head tanks and aluminum radiators present special problems, but for the most part, a really competent radiator shop can work wonders. The last one I had done, this past summer, was a small one, and I had it cleaned and a new neck soldered on. It cost only about $30.

For a larger radiator with complete service, I expect to pay about $50-$75 for an 'overhaul'--maybe more.

Admittedly, there is no reason to clean out a rotten radiator, but it is not always necessary to buy a new one. You have to be a little careful of 'new' ones as well, since I am told that the quality varies a lot.

Any radiator shop that would take your money and not return a high quality repaired product is not professional nor competent.

I think I have to stick to my guns.

I bought a radiator cap first.

Not trying to take side but I'd buy a radiator instead of getting it rotted out.

MIke