JJSweize

Hey guys, I recently bought a 1995 Cherokee, 4.0, RHD but that doesn't pertain to the issue. I will try to be as descriptive as possible.

Finally figured out my oil leak was coming from my dipstick. Losing a quart or more on a 6 hour postal route. Mix of stop and go and about 50mph backroad speeds. Oil doesn't come out when idling, seems to waste the most when driving higher speeds. Also, my oil pressure gauge sits around 3.5 when idling but spikes up to 5. It will go past 5 when driving highway speeds and stay there until I let off the accelerator.

I already checked and replaced the pcv valve that's not really a valve but an elbow thing...

With it off some white smoke comes from the hole... smells exhausty...

Did a compression test, technically in specs but cylinders
2-6 hover around 150, cylinder 1 is 125 to 130. Also cylinder 1 had a really bad spark plug when I changed them a few weeks ago. Noticeably worse than the others. Now just a few weeks after replacing it is black and noticeably worse than the others again.

The jeep runs fine, engine sounds good. Only ever idles rough after my route when I start it to go home because it is low on oil. My friend is pretty good with mechanical stuff and thinks valve seats. I read if I put a teaspoon of oil in the plug hole and run the compression test again and it spikes then valve seats, if not rings. (Might be opposite, I'll recheck before I do it) Is that a pretty sure indicator of the issue? Could there be something else I'm missing? Reason I ask is technically the compression is in specs and I wouldn't think I would have the blowby pressure issue of something in specs and not drastically off....

Thank you for any help!

JJ

Edit** Also may be useful, I'm not seeing much if any smoke from the exhaust... at any time really. Doesn't seem any different from any of my newer cars. I did have a soot and gas smell before I changed the plugs which I'm sure will come back if it keeps jacking up plug 1, but other than that my exhaust seems ok.

Left plug is cylinder 1... only 3 weeks old.

TrailerTrash

Is it coming out of the very top of the dipstick tube? Or is it coming out around the base of it where it goes into the block?

How much oil do you put in?

JJSweize

The top of the dipstick, may be having some come out around the cap as well but it is definitely coming from top of dipstick then of course it gets blown all over since it happens mostly when driving faster. And I'm keeping it in the safe zone. Sometimes just a hair over on days I have to do my route, usually just once a week, so I keep it in the safe zone during the trip.

JJSweize

Well it may be the rings. Piston 1 reached 145 after putting a little oil in the plug hole. Is that pretty much a guarantee that's the issue considering that and the spark plug keeps getting fouled up? I guess I'm just surprised by the amount of blowby with it still being in spec... plus I really didn't want it to be the rings.

If that's the case is it possible to just replace the rings? I have read mixed things but alot of people say you have to do a full engine rebuild at that point. I really don't want to take it to a machine shop and have to spend that kind of money, I only use it for work and only work a couple days a week. I could afford it but I'm tanking more than I'm making.

doublechaz

Sounds like rings. Question is why did the rings fail in that one cylinder? I'm thinking fuel washing. Either way, you would have to pull the head to do the rings. It would be foolish not to at least hit the bores with a hone on that job, but then you would have to pull the crank to clean up the grit from the hone. Then the cascade of while you are there starts. You would want to check the block and head for straight no matter what else as the new head gasket will fail if something is warped past spec. If you kept everything sorted you could put the bottom end back together after cleaning from the hone, but you could check oil clearances and bearing condition and replace. We can keep going with "while you are there" until you have a new blue printed engine better than original.

JJSweize

I know there is alot I could do... i just want the thing to run, without droppinga quart of oil each time and burning through plugs. I'm looking at buying another Cherokee and just swapping engines. The price of some of them is the same or less than doing all that to the engine and at least I'd have more parts...

doublechaz

If you could score a rear end damaged unit with the same engine you'd be square over a long weekend.

cruiser54

So, number one is the only plug looking like that?
If so, pull the plug and put some Marvel Mystery Oil in the cylinder overnight. About 4 tablespoons.
Then run it.