OnlyinaXJ

What I know about the motor in my XJ



The valve cover was leaking like crazy, the oil pan as well, and apparently someone forgot to replace the air filter, the little old lady I purchased my Jeep from was all but completely clueless about its maintenance, but at least she knew enough to keep the oil topped up and have it changed on occasion by her mechanic. With regards to the air filter I don't know if she drove on dirt roads at all or just paved, it ran and I performed a compression check (results as follows, starting with cyl 1, 125, 106, 135, 120, 140, and 115), the results weren't too horrible, except for #2.

My question is how to proceed, option 1: stop where I'm at (includes dropping the oil pan) and just replace gaskets, or 2: get a re-ring kit and simply lap the valves and hone the cylinders. Doing a complete and proper rebuild is completely out of the question right now due to my current budget limitations but I will have the money to do a proper rebuild next year. I am planning on doing a stroker (give or take 4.5L) with the HO head, performance cam, the works, there are plenty of threads on the topic so I'm not asking that question.

For the time being my Jeep just needs to be reasonably reliable for the time being because I want to focus on lifting it, not making it run perfectly, just well enough. My concern is that I have no clue about the extent of damage, if any, caused by not running without an air filter. The cheapest option obviously is to simply change the gaskets for now and press (valve cover, oil pan, intake/exhaust, ect.). I am just curious as to your reaction regarding the effects running without an airfilter might have on my engine.

Next question, I have never seen an upside down oil filter before, is this a common set up, it just seems like an excessively messy configuration for an oil change, of course the oil filter setup on my 02 VW Passat 1.8T is even worse So doesn't all of the oil drain out of the filter every time the engine is shut off and subsequently cause a delay in lubrication on startup? I was an aircraft mechanic when I was in the USAF and so a sludge covered engine is completely unacceptable to me, mind you tactical fighter jets are nasty messy freaking machines but we also meticulously cleaned the internals during maintenance.



I'll post some "after" pictures of my engine compartment once I have cleaned it adequately.

Radi

You aren't horribly, horribly out of spec, (120-150# with a 30# variation) but there is some wear going on. Did you pull all the plugs and block the throttle open? At 220K miles I'd say what you have is pretty normal, air filter or not.
Might consider shooting some oil in #2 and repeating to see what happens. At least you'll know whether it's a valve issue, rings or perhaps both.
I'd worry about bearings more than cylinder walls in reference to dirty intake air. How's the oil pressure? Any knocking or other noises?

If it runs reasonably well, the oil pressure is reasonable and it isn't making scary noises I'd seal it up and drive it, save your money until you can do a proper rebuild. You might only intend on doing rings, but all the "Jumpin' Jehosaphat, look at that will 'ya" stuff will turn it into a bigger project than you intend.

The oil does drain out of the filter, get one with a decent anti-drainback valve. The consensus is that does not include Fram.
Wix (NAPA gold), Mopar, Purolator seem OK.

The valvetrain looks a bit sludgy too. Might consider running some Marvel Mystery oil, Auto RX or something similar in there to clean it up a bit.

OnlyinaXJ

Thanks for the advice Radi, and yes I pulled all of the plugs and the throttle was wide open and I turned over the engine a few times too get a cumulative reading. It definitely is a sludgy looking mess, and thats after running a bottle of Gunk engine flush so I will probably try all three lol. The engine actually sounds fine, it fired right up after I installed new plugs, wires, cap and rotor, I'll just drop the oil pan and clean it out along with the oil pickup and I also have a can of Seafoam intake cleaner as well as Seafoam oil treatment to go with the valvoline high mileage oil, I suppose I better take back that fram oil filter I picked up.

As for the oil pressure I have no idea because the gauge is pegged so I need to troubleshoot that and figure out what my actual oil pressure is, although I obviously have not run it since I drained out the old oil, so perhaps, due to the state of the oil it actually was reading accurately, who knows.

cruiser54

Sounds like a good plan, you guys. Get the Felpro gaskets for the valve cover and oil pan though. The premium ones.

Sure you wanna pull the pan? It may not be leaking. Read the diddy below on oil leaks. I don't think your engine is sludgy enough to warrant pulling the pan if it's not leaking.



　

I'd be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF.

Everybody, who doesn't own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking.

Many mechanics, friends, people on Jeep forums who can’t see your Jeep from where they’re at, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it?

A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don't jump on the RMS/oil pan gasket bandwagon right off the bat.

Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons.

First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber's adage apply here. "$hit flows downhill".

Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first.

Revised 02-26-2013

Radi

You can pop a mechanical pressure gauge on there and see what you have. The problem is most likely a failed sending unit, they often read high when they crap out. Might be some of your leak too.

cruiser54

THIS^^ would be a great first step. The results of this test would really help determine the best path to take.

No4x4Yet

cruiser54

You revived a thread that is over 4 years old.....LOL.

Suprmn

In that case, where is the OP with his stroker build thread? Wonder if the original engine held out for him.