Hi folks. New to this forum, and new to XJ wrenching. I have a 91 Sport that sat in a pasture for a couple of years before I got it, and I'm slowly trying to learn how to do her right.

I was always told when I was young that you can't open up the valve cover on an engine without rebuilding the whole thing, but it's apparent from a few days of lurking here that I was misinformed about that. I want to look inside this engine to see if there's anything nasty from sitting so long, but I don't want to get in over my head and ruin a motor. If I pop the cover off of the 4.0 is anything going to spring out at me?

Also have a LOT of oil on everything. Hard to see where the leaks are when everything's covered with oil. How do I get that sludge off so I can diagnose?

Thanks

 

I am not an expert, but I would first get a Haynes manual, and a Factory Service Manual (FSM - look on ebay for one). I did a search on Cherokee 1991 under manuals and literature and got lots of hits.

http://motors.shop.ebay.com/i.html?_...506.m270.l1313

That oil all over everything did you a favor by preventing rust.

 

Removing the oil fill cap in the valve cover and shining a flash light down inside will tell u what things look like for the most part.

Engine degreaser, a wire brush and a roll of paper towels will clean it up good.

 

just dont try to wire brush the grease lol. Slipped off something I was wire brushing into engine grease on the side, had to parts washer my brush lolll.

 

yes, get a haynes manual at auto parts store, study it.

NO, nothing will spring out at you if you remove the valve cover.

piece of advice,,,,,,

is the near a spot where you have access to a hose and a sprayer?

use two cans of Gunk engine cleaner, spray all over the motor and stuff....

wait twenty minutes,,,,use hose with sprayer and rinse off....

then take off valve cover to look at valve springs and inside the top of the head.

use another can of gunk and sray the entire inside of the valve cover while its off and rinse with the hose in same procedure as above.

clean off all gasket material using a putty knife being careful not to gouge out any of the metal... put a new gasket on.

thats a start, read the manual to get familiar with the jeep. How many miles on it?

my 91 has 265 thousand miles on it and runs great.

good luck!

cpnwrench

 

217K on the clock. Still has tons of power. AT shifts well, engine feels great at highway speed. Feels rough around town. Engine has a grumble to it at lower RPM and sounds like it's going fall out when I turn on the heater or air conditioner.

I also have some lifter clatter that comes and goes. The most reliable way to calm the clatter is to get on the highway and drive above 65 for a while.

 

For the oil and grease, get a couple cans of Gunk Foamy Engine Brite and get ahold of a pressure washer (the coin-op car wash and $5 in quarters will do). You want the engine warm but not HOT, spray your dirty areas with the engine brite until they have a good cost of foam on them (it will dissolve at first so be generous with it), let it soak for several minutes, then blast it with your pressure washer. You may need to repeat the process 2 or 3 times for heavy grease buildup, or get a sturdy scrub brush and go to work (a wire brush works great on the engine block but don't use it on painted surfaces. if there's thick grease buildup plan to throw the brush away after). Be careful not to direct high pressure water at electronic components like your distributor, alternator, or ECU.

As for your valve cover, there's no harm at all in pulling it to have a look inside. But get a new gasket first, because the old one will likely come apart when you remove the valve cover.

 

Hit the engine with a first pass of Gunk and pressure wash. At first glance it appears I have an oil leak near the oil filter, and judging by the grease buildup she's been leaking from that area for a long time. A quick search of the forum tells me this isn't uncommon.

Any body reading this dealt with this sort of leak? Anything about the solution surprise you? Anything you found particularly challenging? The last thing I want to do is try to fix this leak and run into a problem that grounds my ride.

 

If its the oil filter adapter leak it's pretty straightforward. The only trouble is trying to break the torx bolt since its red loctite. It's pretty easy though, just get it out and replace the o rings, which you can find from the dealer for $5-$10. There are a couple write ups on here if you search.

 

You said it sat in a feild for a couple years , first thing I would look at is what kind of shape the unit-body and floor is in. If the thing is shot than nothing else matters it's a part's jeep. good luck.

 

Tore the carpet out under the back seat today, found a little surface decay by one plug but the metal is still in great shape over all. A tiny bit of rust on the drivers door, otherwise the visible exterior is rust free. I'm going to pull the carpet in the cargo area this week, might pull the rest of the carpet altogether and lay down bed liner.

 

The belt seems to be whole lot squeakier since I degreased stuff.

 

Well Nate, sounds to me like you have a pretty good vehicle there.

as the other guys said,, replacing the oil filter housing gasket is pretty straight forward,,,but......

I went to Jeep dealer and got the gasket (s)...1 for the oil filter adapter and 1 for the oil filter housing itself ( like 15 dollars total).

I did mine in 2002 and no leaks at all. ( i have same yr and model but with a 5spd).

and as a side note,,, replace all the fluids etc etc... flush out not only the radiator and engine, but a separate flush of the heater core....

clean up and re attach all the ground connections you can find, and be on the look out for any wires in the engine compartment which may have been in direct contact with the motor, (might have some melting (you may not, but it doesn't hurt to inspect.).

change all the hoses and belt too!

am not sure if you are going to drop the gas tank to eliminate any crud inside there, but if you do, change out fuel filter, and check out your brake pad wear and the condition of the brake mastercylinder fluid......

I tell ya, I have had mine twenty years and it really does run great. THe guys on this forum are really great in helping as long as you can define what you are experiencing,,,,as its tough to troubleshoot something without a good explination.....but yeah best of luck with it, you will find it is an EXTREMELY DURABLE vehicle...!

Cheers!

cpnwrench

 

I hope you changed the oil...
Run it for 500 mi with new oil, add in a quart of seafoam or ATF, run about 20mi, Then drain hot..
Your lifters are pry full of gunk.

 

I'm on my third oil and filter change since I got it. Got about 300 miles on this batch, was going to do the Seafoam change this weekend whether I hit 500 or not.

I love this car. Right now it's kind of a heap. Interior is in bad shape, 1 fender and the grill are crunched, 2 windows cracked to hell. My wife literally WILL NOT ride in the thing. But I can't stop driving her.