Diagnosing a head gasket
#1
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Year: 1999
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Diagnosing a head gasket
I've owned a 99 Cherokee for the last five years. When I bought it with 56,000 miles on it, my mechanic said the freeze plugs had leaked in the past and the exhaust manifold had a minor crack. Perhaps it had overheated. I ignored that stuff for the last 30,000 miles. Over that time, I would periodically have to add coolant. I also replace the water pump and therostat. A few months ago, a spark plug cracked and when my mechanic replaced it, he said the head gasket between cylinders 2 and three was leaking. A compression test showed those two cylinders had 120 and 140 pounds. He wanted $900 to replace the gasket and do a valve job. I trust this guy a lot, but I'd rather not spend the money. My thinking is that this engine has always had a small head gasket leak and that maybe I could just keep a close watch on the coolant and ignore the problem. I just drove it 250 miles, including climbing over the 4,000 foot El Tejon pass, without a problem. Is it possible that a head gasket leak does not progressively get worse?
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Year: 1991
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I've owned a 99 Cherokee for the last five years. When I bought it with 56,000 miles on it, my mechanic said the freeze plugs had leaked in the past and the exhaust manifold had a minor crack. Perhaps it had overheated. I ignored that stuff for the last 30,000 miles. Over that time, I would periodically have to add coolant. I also replace the water pump and therostat. A few months ago, a spark plug cracked and when my mechanic replaced it, he said the head gasket between cylinders 2 and three was leaking. A compression test showed those two cylinders had 120 and 140 pounds. He wanted $900 to replace the gasket and do a valve job. I trust this guy a lot, but I'd rather not spend the money. My thinking is that this engine has always had a small head gasket leak and that maybe I could just keep a close watch on the coolant and ignore the problem. I just drove it 250 miles, including climbing over the 4,000 foot El Tejon pass, without a problem. Is it possible that a head gasket leak does not progressively get worse?
a radiator shop can test to see if you have combustion gasses getting in the water
but if you are not having a over heating problem then I say no you don't have a bad head gasket
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theres a pump your attach onto your radiator... you pump up the pressure and let it sit under pressure for however many minutes... it should no bleed down beyond a certain amount... if your mechanic did not do this test then you need a new mechanic with some real tools man... its easy and youll kno for sure if theres a leak in your coolin system... look at the bottom of your oil cap... see milky substance? if so then got water in the oil... bad head gasket... if not then doesnt mean it still isnt bad... run the pressure test... thats what all mechs do to test for head gaskets... I was a tech for Nissan...
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Year: 1991
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Sounds like (if it really is burnt) it is just burnt beside the cooling duct that runs through the head. If its not over heating and you don't mind adding some coolant every now and then it's not an imediate problem. It may get worse over time with coolant comming through that burnt section, but you've got some time to save up some money .
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I have no reason to doubt the diagnosis was right. There were combustion products in the coolant. I also believe the mechanic did a leak down test. So, my question is whether a head gasket can leak a small amount and not get progressively worse? Or am I asking for more trouble down the road by ignoring it. Thanks for the replies.
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Year: 1991
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I have no reason to doubt the diagnosis was right. There were combustion products in the coolant. I also believe the mechanic did a leak down test. So, my question is whether a head gasket can leak a small amount and not get progressively worse? Or am I asking for more trouble down the road by ignoring it. Thanks for the replies.
yes it could last forever
or it could cause major damage
if you trust your mechanic stop asking questions on a forum and go with what he tells you needs to be fixed
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Mike. what's your beef? My mechanic said it was up to me. He doesn't fix that many Cherokee's and I thought I could find some friendly advice here, not a snotty attitude.
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jeep
I have an 89 that I had the same problem with,I was adding water about once a week and was not sure what the problem was until just before it went. If you depend on your jeep daily or plan on a any long trips,replace it. head gaskets that start to leak do not last forever,all you have to do is overheat it once and it could go out completly. It takes about 6hrs from start to finish to replace the head gasket,$900 is cheap and if you are getting the valves done also even better.
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Year: 1987
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Engine: 4.0 Renix HO. head
just to get the valves done is 150$. then add in the gaskets, Labor, etc and your getting it cheap. I got a quote of 1300 here and they would have the jeep for two days. If the coolant is getting into your oil or if it is just leaking into the cylinder its causing damage already.
ive seen bad gaskets last a while after adding stop leak. But at the same time Ive seen them deteriorate at a rapid pace and destroy an otherwise salvagable motor.
If you trust your mechanic then I would suggest going for it. Things like that always tend to fail when you need your vehicle the most...
ive seen bad gaskets last a while after adding stop leak. But at the same time Ive seen them deteriorate at a rapid pace and destroy an otherwise salvagable motor.
If you trust your mechanic then I would suggest going for it. Things like that always tend to fail when you need your vehicle the most...
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I was not trying to be snotty
you you asked for a direct answer to a question that is not answerable
so I gave you the most direct answer I could
I could also say you have a snotty attitude by your remarks
but I'm not going to judge after two post
good luck with your repairs
you you asked for a direct answer to a question that is not answerable
so I gave you the most direct answer I could
I could also say you have a snotty attitude by your remarks
but I'm not going to judge after two post
good luck with your repairs
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Year: 1991
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When I did mine I got a rebuilt head for $150, a gasket kit for $50, and did it myself. It really doesn't take much more than common sense and little mechanical knowledge to change a head on one of these things. It takes a day and a half and have a friend bring over a case of beer and have fun, save yourself $700...
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.... he said the head gasket between cylinders 2 and three was leaking. A compression test showed those two cylinders had 120 and 140 pounds. He wanted $900 to replace the gasket and do a valve job. I trust this guy a lot, but I'd rather not spend the money....Is it possible that a head gasket leak does not progressively get worse?
Last edited by Programbo; 07-10-2009 at 09:05 PM. Reason: Spelling error
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I just want to thank everybody for their advice. I have decided to go ahead with the head gasket job. Even though it has been leaking coolant for four years, the gasket will blow some day. And since the engine only has 80,000 miles on it, I am hoping I can get some good use of it still.