Eagle

The seal inside the master cylinder is leaking. You'll have to replace the master cylinder.

The 0331 heads were the first to have the bosses for mounting the coil-on-rail coil packs. All 4.0L engines before 1999 for the Grand and 2000 for the XJ used a conventional coil. If the head doesn't have mounting bosses for the coil pack bolts, it's not an 0331.

He replaced them. Does act like a secondary ignition issue though. Sorry -- I missed that.

Check your spark plug wires. If they are the originals, the insulation may have broken down and they may be losing spark energy to any metal they pass near. When this happens, it feels like a misfire -- mostly because it is a misfire.

The gears and chain should be the same, from what I've seen. For reasons known only to some AMC engineers who may be long dead, the deck height on the 2.5L is just a bit less than on the 4.0L, so a timing chain that would be taut in a 4.0L is slack in a 2.5L. So for the 2.5L they used a tensioner inside the timing cover. It's not uncommon for the tensioner to wear out before the chain.

We're talking about spinning the oil pump shaft with a drill, not the engine.

How is an oil pump going to start picking up oil if there's nothing between the gears but air? What you are describing is a self-priming pump, and automotive oil pumps are not self-priming.

Things haven't changed that much. The AMC FSMs from the mid-1960s said to pack a new oil pump with Vaseline as a way of getting a prime.

Pretty neat. I wish I had known about that twenty years ago.

Not in this corner of the world. At least, not when I was crewing on the stock car. Even a new engine that we knew had assembly lube on the cam, cam bearings, crank and rod bearings, and cylinder walls got the oil pump spun over with a drill until we had positive oil pressure. Until we saw oil pressure, the engine was only cranked over by hand.

That's incorrect. The early 4.0L engines used a multi-part pan gasket that had to be sealed with silicone where the parts met. Often, it didn't work. Somewhere in the 90s Jeep changed to a one-piece pan gasket. The newer gasket works on all years and is far superior to the old, multi-part gasket.

If the oil pump has lost its prime, I don't see how spinning the shaft with a drill is going to help anything. All you're doing is trying to pump air with a pump made for viscous liquids. But -- whatever you don, DON'T crank the engine any more. The cylinder walls are dry, the bearings are dry, the camshaft is dry ... everything is dry, and has no lubrication. See if you can rig up some Rube Goldberg arrangement to force feed some heavy oil back through the oil pressure sender hole to get oil back into the system, then try spinning the pump with the drill.

The tenth digit of the VIN is the year. But ... the VIN system changed from 1988 to 1989. Explained here: http://www.allpar.com/mopar/jeep-vin.html Your VIN is 1 J 7 F T 3 6 L 3 K L 445397 1 = Country of Origin (USA) J = Make (Jeep Company) 7 = Vehicle Type (Truck) F = Gross vehicle weight (4,001 - 5,000 pounds) T = Model Line (my FSM says T is a 2WD Cherokee) 3 = Trim Level (Pioneer)(Another source says Chief) 6 = Body Style (???) L = Engine (4.0L) 3 = Check Digit K = Model Year (1989) L = Assembly Plant (Toledo, Plant #1) 445397 = Serial number This site makes it easy, but isn't specific as to how they do it: https://www.decodethis.com/vin/1J7FT36L3KL445397 I've looked into three different FSMs and about six web sites. They are NOT all consistent as to what some of the code mean. They do all seem to agree that you have a 1989 Jeep.

Considering that Santa Claus is between 500 and 1600 years old (depending on which tradition you regard as correct for his origins), he's probably seen a few things ol' Timmy hasn't even thought of yet. It's like they say, age and treachery beats youth and vigor every time.

Even if it was a Comanche? Or especially if it was a Comanche? :) A 1971 Comanche would be quite rare ...

Unless you are certain that you'll never want to use a pickup again -- keep it. The 4-cylinder, 4-speed, 2WD is not a desirable model. I don't really know what it's worth -- my guess would be $1,000. Even if it's $1,500 ... look at prices for used S-10s and Rangers, check the prices, and then look at the mileage and condition. As Frank the Dog wrote, "You can't by anything at twice what that truck is worth that'll be half as good."

I forgot that Hornbrod had already posted instructions on running that test. If the printed circuit is damaged, it should be possible to run jumper wires from the harness connector on the cluster directly to the two terminals on the gauge. But first ... find out what the problem is.

No, now it is time to look at the wiring between the gauge and the sending unit. Do the test suggested -- find the plug where the fuel pump/sender harness pigtail connects to the chassis harness. Unplug it. Turn on ignition. See where gauge reads. (Should be Full) Then identify the wire in the chassis harness side for the sender input. Connect to ground. See where gauge reads. (Should read Empty.)

Does Carfax provide actual owners' names? To be honest, if some stranger called me about a vehicle I sold years before, I'd hang up on them.

Not just off-road. Remember, I made the mistake of buying a '99 WJ V8, which had that axle. It didn't say it in the owner's manual, but in the factory service manual it specifically said NOT to jack the vehicle with a shop jack under the rear pumpkin. After some research, I finally found that the reason is the reverse strain of having the weight supported on the pumpkin with the springs pressing down on the outer ends of the tubes warps the housing, resulting in gear noise and premature wear. In addition, the internals don't interchange with a "real" Dana 44.

That doesn't look like any Dana 44 I've ever seen. Is that by some chance a ZJ Dana 44 -- with the aluminum housing? If so, don't touch it.

An MJ main leaf will give lift to an MJ, just as an XJ main leaf gives a lift to an XJ. In the XJ, using a second set of main leaves with the eyes cut off results in 1-1/4 to 1-1/2 inch of lift. The same is reported to be the case for the MJ. To get additional load capacity without adding lift, you need an AAL that matches the loaded (at empty curb weight) arch of the springs, not the free arch.

I don't know what you think you saw, but there was never a Metric Tonne" package for the XJ.

There's one caveat -- the MJ never had rear disk brakes, so the conversion might have changed the overall width. In stock, drum brake trim, the XJ and MJ rear axles were the same width, although the spacing of the spring perches was different (as well as one being SUA and the other SOA). The "posi" is probably a factory Trac-Lok, so you should assume that the clutches are worn out and that it will need a rebuild kit. I think those are running about $100 these days -- maybe a bit more.

I haven't gotten around to verifying it yet, but I believe that a cut-off XJ main leaf would be perfect for adding carrying capacity without adding lift. The key is to find an AAL that has approximately the same free arch as the MJ springs have when sitting at curb weight (unloaded). Unscientific eyeballing tells me that an XJ main leaf should be about right, but I haven't actually crawled under one of my MJs with an XJ leaf in hand to compare. There is no reason why an XJ AAL would make the ride harsh. I've done the XJ AAL using cut-off main leaves twice, and the resulting ride was very comfortable. I see no reason why it would be any less comfortable in an MJ. Keep in mind that the XJ uses 5/16" center pins for the springs, where the MJ uses 3/8" pins. You'll probably have to drill out the holes if you use XJ leaves.