Coolant hose rupture

[JimN]

Hello everyone, this issue has been going on for some time so any thoughts would be appreciated. I've got a 2000 Series II. About 6 months ago sitting in park with the car running a coolant hose ruptured. I replaced the hose and had the system checked. The mechanic flushed the radiator, checked the system and claimed everything was fine. After this I noticed that occasionally the car would run hot, usually when sitting in traffic or when driving locally. Back to the mechanic, who ran it and checked the coolant (topped it off) and again said it was fine. He said to watch it and if things continued this way to bring it in and we could change the thermostat, that maybe it was sticking. The problem continued on and off but for the most part the temp was fine with occasional spikes. I did not have the thermostat changed.

Yesterday after a short drive (1 mile) the temp was fine. I parked at my office, walked inside and noticed smoke from my engine. Went outside and was greeted by a big puddle of coolant under the car. Checked under the hood and found another ruptured coolant hose. Both this rupture and the earlier one were not just pinhole leaks, the hose actually burst resulting in about a 2" tear.

Some other things I've noticed that might be associated with this:

1 - coolant level seems to be slowly dropping but I can't seem to find a leak anywhere.
2 - when I open the coolant reservoir to top off the coolant it bubbles up with air escaping from the system...normal?
3 - at times when accelerating from a stop you can hear coolant rushing through the system behind the dash - seems to indicate air in the system?

Any thoughts??? Thanks for the input.

[jmrivera]

To anser your questions:
1). you have a leak, but may be associated with the bad t/stat
2). normal, for me at least
3). your mechanic needs to vent the air out of the cooling system using the bleed screw.

You have a bad t/stat, that' s why you keep blowing hoses...

I suggest you replace all cooling hoses and the t/stat ASAP, and if your local temps get above 90 degrees, a coolant additive like Water Wetter or Purple Ice...

[DailyDrivenTJ]

You could have head gasket leak.

From my first hand experience on a Jeep WJ (Grand Cherokee with 4.7L) it had a blown head gasket and kept balloning up the radiator hose. Mine did not blow up but it was enough to cause a leak around the clamp.

Blown head gasket easily explains your disappearing coolant without a trace and air bubbling. The exhaust gas is escaping through the head gasket into the coolant and this also builds up pressure inside of the cooling system.

If it is simple air bubbles trapped inside of the cooling system, it needs to be burped out which can also cause overheating problems, but it won't burst radiator hose.

[Disco Mike]

Jim,
Quit driving the truck till you get someone who cqan properly check it, if you don't you may go to an overheat that your engine won't recover from.
Mike

[auwesman]

How many miles are on your truck?
If one hose blows, its usually safe to go ahead and replace them all (if ones weak, they're all weak) and the T-stat isn't very expensive so replace it also.
If you can't find a leak, have your mechanic pressure test your system....he should be able to locate it.

I'm not sure why people put off hose replacement (not saying you did, just in general). So much can go wrong when you loose a hose! It should be a part of every vehicles "prevenative" maintainance plan.