Unexplained Coolant loss

Probably a leak either at the head gasket or small crack or hole between the cooling system and a cylinder. Have them pressurize each cylinder with a leakdown tester (engine hot and cold) A leak will be indicated with a rise of coolant in the recovery bottle. The reason I say perform it hot and cold is that the leak may only occur at either hot or cold but not both.

Bill

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Well, I took it in Monday afternoon with less than a week since the last time in. The reservoir bottle was empty and the mechanic topped it off. A discussion with the service manager and his boss has resulted in an agreement that the next time I come in to re-top the bottle, that I would leave it with them to have another look see. I myself did not find any leaks on the water pump or hoses anywhere. They didn't see anything either... So I think this time around they will pull the head and check for cracks and flatness.

Brian

If it were me, I would have the engine oil analyzed for coolant. It is a cheap test (about $15) and would indicate if the coolant is entering the crankcase somehow. Coolant in the oil will cause a lot of problems.

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Hi Mike,

The dealer has been reluctant to do anything but a pressure test. I guess he follows the standard procedures Jeep has set forth. I got the "99% of all problems are found with the pressure test" from the service manager. I told him that just maybe I could be the 1% since you haven't solved anything yet!

The jeep goes back Monday again with 100 miles and 1 week since last time they filled the recovery bottle. They will keep it this time and look deeper into the problem.

I'd hate to have them destory another shortblock, because they haven't looked at the head yet.

Brian

Thanks, to all who responded. Got my XJ back on Friday and dealer had replaced the head. They did not see anything wrong visually, but the dealer sent it out to a machine shop and they found a crack.

Brian

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