1988 Areostar Overheating

What is the question? Why are you bothering the previous owner? This isn't his problem, especially after driving for many weeks with no problems. Did you expect him to fix things that hadn't broken yet?

Radiator hoses pop all the time. Auto parts stores are full of them because people are buying them. The fact that an old hose popped a leak is proof there had to have been pressure in the cooling system, and that means there were no leaks at that time.

The concern here is driving for ten minutes after hearing the hose blow out. You should have seen the temperature gauge rising. Ten minutes can do a lot of damage to an overheating engine.

It sounds like your concern is over the $8.00. If that was for some magic leak sealer, you got what you paid for; a can of chemicals, and nothing more. I'm not understanding what else you expected or what other running problem you're referring to. The rest of your description is real hard to make sense of.

"The next day I phone the owner... "

I understand now that eight bucks was just for the leak-stopping chemical, and you paid separately for the hose repair, but you didn't actually say that at first.

My first concern is why a chemical was added. While it may not hurt anything, as I mentioned previously, the hose popped because there was pressure in the cooling system, like there is supposed to be. That means there was no leak up to that point. Normally we would replace the hose, recommend they all be replaced if they weren't recently since they all rot at about the same rate, refill the coolant, burp the air out of the system, and send you on your way.

The fact there is an overheating problem now leaves two conditions to consider. First, the ruptured hose could have been caused by a problem that just started while you were driving a few days ago, and it was the first casualty. The underlying cause could still be there. Most commonly that would be a leaking cylinder head gasket, although your engine is not noted for that. Regardless, your mechanic can perform a chemical test at the radiator to check for that. It only takes a few minutes. The test involves drawing air from the radiator, while the engine is running, through a glass cylinder with two chambers partially-filled with a special dark blue liquid. If combustion gases are leaking into the cooling system, that liquid will turn bright yellow.

The second thing to consider is the current overheating problem is the RESULT of the blown hose. The most common cause for that is air in the system that didn't bleed out by itself, but that should have occurred by now.

The first thing that must be done is to determine where the coolant is leaking from. I have a suspicion it is simply running out of the overflow bottle. That is not exactly a leak. Coolant is supposed to go into that jug when the engine warms up, then it gets sucked back into the engine when it cools down. During overheating, too much coolant goes into the bottle, and it can be boiling. That will make it spit out the overflow tube and can make a mess.

If testing does not indicate a head gasket is leaking, other suspects include a radiator that's blocked by a butterfly collection or some other debris, cooling fins corroded off the radiator, (this is more common in northern states where they throw a pound of salt on an ounce of snow), or a thermostat that's stuck closed. Check for proper radiator fan operation too. A problem with that will cause overheating at slower speeds. The fan is not needed at highway speeds because natural airflow is sufficient to cool the radiator.

Yup. Be warned though, I had a major house fire two years ago, so now I have to drive into town to use my library's wireless internet. I may be here every day or every other day. Don't assume I'm ignoring you. Sometimes I'm here early in the morning, and sometimes late at night.