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93 XJ low compression, what are my options.

Took my '93 XJ 4L with 190K miles on into the shop because it was blowing oil into the air filter and the crankcase ventilation system is working fine. Mechanic told me the compression was getting low. Come to think of it it does seem to have lost some power over time, although it's hard to tell.

What would be my best option here? Get a new vehicle? Have a rebuilt engine put in? Have the present engine fixed? Ignore the problem until it breaks down?

It's not blowing blue smoke, it leaks a little from the main seal and the valve cover gasket, and opinions vary on whether the exhaust manifold is cracked or not. Near as I can tell nothing around the engine has ever been worked on. Any suggestions what to do are apreciated...

Reply to
Monte Castleman
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"Compression was getting low" is super vague. There are six compression readings on that engine and knowing what they are can tell you a lot. If they are all low and equal, and they come up with a squirt of oil, then chances are good that you need a ring job. However, bad valve stem seals can mimic the same symptoms as bad rings, and are a whole lot easier to fix. One or two low compression readings can mean a need for a valve job, also cheaper and easier to fix than rings. Try to get your mechanic to say whether the rings are bad or not. He's the one with access to the vehicle who can make this determination.

My Suburban was blowing a quart of oil every 300 miles, but no blue smoke. In fact, I had installed two three quarter inch aftermarket breathers in each valve cover just to get it out from under the hood. It definitely had bad rings, so you never know by the blue smoke or not.

Earle

Reply to
Earle Horton

Reply to
L.W. (Bill) Hughes III

You do have a way with words......

Reply to
Bodhi Bhagg

I would start by pulling off the plastic line that runs to the rear of the valve cover at it's manifold end and see if i could blow through it into the valve cover. If I couldn't blow through it, I would know the 'mechanic' was a liar trying to sucker me for a new engine.....

That line can be cleaned with carb cleaner and the rubber grommet's hole can be cleaned with a paper clip. In some cases, the valve cover has to come off to get the sludge out of the grommet's way.

Other than that, I would want to verify just 'what' was causing the low compression. A wet test can tell lots, so can a leak down test.

Mike

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M> Took my '93 XJ 4L with 190K miles on into the shop because it was blowing

Reply to
Mike Romain

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