Bad news on the Valve Seal Replacement - Need advice

I Checked my plugs and #2 is wet with oil. All the others have an oily film around the base of the plug by the element but the area of the spark plug gap looks fine. The engine sounds ok when it's running.

When I first changed the seals I let it idle for a long time and didn't see any oil. Then I took it for a drive and didn't get a chance to check the plugs until today because of rain. That's when I got this results.

Questions: Does the oily film around the base of the plug (at the bottom where the thread ends) sound normal or bad?

Could I have partially blown the head gasket around #2 to get this results?

I'm not seeing any water in the oil or vise versa.

I need advice on what direction to take now. Leak Down test?

Thanks,

Reply to
William Oliveri
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Reply to
L.W.(ßill)

I don't know Bill, when I did the valve seal replacement #2 was the first one I did and I found it difficult to find the compression stroke by placing my finger in the spark plug hole while turning the crank. That is, I didn't feel compression as strong as the others. Actually, it was much weaker. Then, later, I didn't try to find TDC and just undid the valve bridge as recommended so the valves were closed.

Bill

Reply to
William Oliveri

Reply to
L.W.(ßill)

Our local auto parts stores sell compression testers for less than ten bucks.

Do a compression test dry and if they are all the same, drop the tester fast and back away slowly, very slowly...... ;-)

If one or more are low, toss a tablespoon of oil into the spark plug hole and test that low one again. If the compression comes way up, you have bad rings, if the compression stays low and only moves a couple lb, you have a bad valve or cooked head gasket.

If two side by side are low, it's the headgasket between them usually.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

William Oliveri wrote:

Reply to
Mike Romain

Reply to
Steve G

Hi Steve,

The initial problem at the serious level seemed to crop up after I went on my first 4 wheeling trip since I've bought this jeep and that problem is I was blowing blue smoke out of my tail pipe. Several weeks before I went 4 wheeling I had the jeep in another shop to try and detect the source of a noise and that guy told me I was blowing blue smoke but didn't give me an idea where it was coming from. Also, I have been burning about a quart of oil every 1000 miles or so.

The problem blowing blue smoke which occurred after idle for some minutes and then pressing on the gas. I could not see blue smoke when driving at any speeds but when I came to a stop light and idled for a couple minutes then pressed on the gas I could see a puff of blue smoke. Also, most of my plugs looked like they had a wet, oily film around the base of the plug and the element looked black. These were relatively new plugs.

At one point I had to have the jeep towed because it stalled and I couldn't get it up again. I had it towed to a shop who was already closed for the night so I decided to change the plugs and see what happens. It started right up after that so I skipped the shop and drove it home.

Later I had that same shop do a compression test on the engine. The shop told me that he had readings of 150 psi across the board, no variation in pressure.

The shop only did the dry test as far as I know.

So, with the compression test and the nature of the blue smoke being at idle I went for the easiest, least expensive fix which was to change the valve seals.

Now, #2 cylinder was the first one I did and I did question the sound of air leaking from the cylinder when I applied air pressure. I looked for air coming from several different places, tail pipe = none, radiator water = none, I put the valve cover back on and could feel air coming from the PCV valve hose - it was light but I didn't have the other vent hose which goes to the air filter closed off. I changed cylinders and got the same noise so I suspected this part was normal and continued on with my valve seal change.

After completion I didn't see any blue smoke at idle and still don't. I let the engine idle for about 20 minutes and still no smoke. I then checked the plugs and they all looked great, absolutely no oil or film. Then I drove it for about 10 - 15 miles and the weather got rainy so I parked it. Then yesterday I checked the plugs and found #2 wet. The others have that oily film around the base of the plug (at the end of the thread on the bottom) but the element is not wet. Only #2 look so bad. When I drive it it seems ok but I want to get another set of backup plugs before I venture too far from home.

So now I'm going to perform a compression test my self and see if I can get a leak down tester and do that too.

Thanks for any additional suggestions,

Bill

Reply to
William Oliveri

Krapp, where do you shop for parts? I haven't be able to find one for less than 50.00 around here, yet.

Anyway, That is my next thing to do.

Thanks,

Bill

Reply to
William Oliveri

LOL..

A place we call krappy tire!

Seriously.

I just checked and the tester is $21.00 CDN which is just over ten bucks US.

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Reply to
Mike Romain

-Brian

Reply to
Cherokee-LTD

It does sound like worn guides or rings, I would attach a vacuum guage and read the measurement at idle, along with fluctuation range. This should tell you if its guides or rings. The Vacuum guage is almost a lost diagnostic tool, but can identify a lot of problems.

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could also remove the oil cap from a fully warmed-up engine and see if acloud of smoke comes out.If you had bent a valve, you would know it.

Reply to
Paul Calman

I did check the guides manually when I changed the seals by dropping the valve a bit and moving it back and forth. The worst offender by far was #1. #2 was no movement at all. #1 looks fine from the spark plug point of view compared to #2.

Bill

Reply to
William Oliveri

Bill,

Take the advice of the others and get the compression tester, vacuum gauge, and the leakdown tester we discussed previously. These three tools are invaluable for diagnosing engine condition and tune. The vacuum gauge can tell you more about the condition and tune of your engine than any other tool for the money. Buy one that has an undampened needle though. This will make it easier to see the fluctuations in vacuum, which will aid in carb tuning, or detecting misfires, sticky piston rings and leaky valves. It seems that you are trying to learn more about doing your own auto repairs, and these are tools that every auto mechanic should have. They will pay for themselves in saved time and by reducing improper diagnosis of problems.

As far as your problem, you can have good compression and still have oil control ring that are not doing the job. I'm not saying this is what it is, but it is possible. Did the engine sit for a long period of time before you bought the Jeep? If so, the sticky ring theory is very possible, but diagnose it first. Also, check your PCV system to make sure it isn't somehow allowing oil into the intake system. A faulty PCV valve can do this. If the engine truly does have equal pressure in each cylinder, then I would put some miles on the Jeep and see if it clears up. Sometimes sticky rings clear themselves up after a little running, but the engine needs to be in a good state of tune, or you'll experience carbon buildup which may not allow this to happen.

Chris

Reply to
c

Hi Chris,

I have a compression tester and I ordered the Leak Down tester today. I will look into the vacuum tester too.

I'm not sure of the engine's history before purchase. The guy before me blew something up when he drove it and it ran out of water, thus over heating. Then he put water on the block to try to cool it off faster. This resulted in engine damage so he limped back to Santa Monica and had his garage replace the engine with a used one (don't know why he did that because he spent well over 2k. Should have put a remanufactured engine in it for that $$$).

I checked the PCV and the intake and didn't see or feel any oil in those areas.

I have the MPI Kit on it with the timing correct so as far as I know it's in tune.

What is a sticky oil ring mean? Does that mean the ring gets gunk around it and doesn't move correctly?

Thanks,

Bill

Reply to
William Oliveri

Reply to
L.W.(ßill)

Hi Bill,

Haven't had a chance yet to test it myself. I had a mechanic test it before because I wanted a professional opinion of the state of the engine (which I didn't get) and because I was unsure of the process. He's the one who gave me the 150 readings before.

I'm going to work though understanding the process and get it done before this weekend. Doesn't look too bad.

Bill

Reply to
William Oliveri

I think this is missing clue. Overheating an engine will cause the rings to loose their temper and for the oil rings to clog with coke. I am pretty sure you are going to be holding them in your hand before this is fixed. The good news, it's a job you can do without removing the engine or crankshaft , and the engine is probably not "shot". On th other hand, oil is cheap, but if it fouls plugs you cant use it much longer that way

Reply to
Paul Calman

PS, I commend the former owner for having the personal integrity to tell you of the overheating.

Reply to
Paul Calman

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