Eagle

Just to hijack a bit ... what years had the aluminum valve cover? I've never encountered anything other than plastic ... and I HATE plastic.

Get enough advice and somebody pretty much has to be right! :)

I don't know, either. I haven't sawed a ZJ proportioning valve in half so I have no idea how it works.

Yep. My '87 MJ has the dealer-installed a/c.

Pete, he didn't ask why the headlights were upside down. Whatever he intended to ask, what he did ask was IF they are upside down. ]

Your post (#4 in the thread) was hardly polite, to either me or to Hornbrod. If that's your idea of "polite," I don't want to hang with your group of friends.

Look at the headlight lenses. There are codes molded into the glass. If you can read the codes, the lamps are not upside down..

Why would you need weld-on shock mounts? Did you remove the stock shock mount studs? MJ shocks don't use bar pins, why would you need bar pin eliminators?

There are several threads here that describe how to eliminate the load-sensing proportioning valve. As I posted just yesterday (or maybe the day before), IMHO replacing the MJ front metering block (it is not a proportioning valve on the MJ) with an XJ proportioning valve is a VERY bad idea. To understand why, you have to understand how the XJ proportioning valve works. In the XJ proportioning valve, fluid to the rear brakes is routed through the forward part of the valve body. Inside that, there is a spring-loaded plunger with an o-ring seal on a piston. The spring is VERY strong, and until the brake fluid pressure gets high enough to overcome this spring, there is NO braking to the rear wheels. Once the pressure gets high, the plunger moves and the rear brakes come on. This is why XJ rear brakes typically last through two or three replacements of the front pads -- the rears never do any work in normal driving. But the rear of an XJ has a full roof, rear seats, a lot of glass, and a tailgate hatch. There's a fair amount of weight on the back wheels. The rear wheel load in an empty MJ, by comparison, is very light. In normal conditions you won't notice a difference with the XJ proportioning valve because the rear wheels are doing anything, but under panic conditions the rear wheels could lock up unexpectedly. That's "not a good thing." Of course, if you correctly bypass the MJ height sensing proportioning valve you'll have full braking power to the rear wheels all the time, and that can also lead to premature rear wheel lockup under panic conditions. Being an olde pharte who learned to drive decades before we had proportioning valves, I can live with this because at least it's predictable, where the operation of the XJ proportioning valve is not. (The XJ valves also clog up. My '88 XJ has had no rear brakes for four or five years, but it's driven only locally so I haven't made a priority of fixing it.) For those who can't handle that, the Wilwood adjustable proportioning valve for the rear wheels is the way to go. Do NOT use an XJ proportioning valve. IMHO it's an exceptionally stupid design.

Now that you mention it, I recall a few years ago discussing this with the owner of a commercial spring shop where my friend used to have his stock car springs made. They don't drill springs for the center pins -- they punch them. The more I think about it, Don, the more I think you should just replace with whatever size is in there and keep the u-bolts torqued.

Something looks screwy about that wiring diagram, but I don't have my FSM handy to refer to. Just doesn't look quite right. Anyhoo -- does the fan run with the speed switch in the HIGH position? That position bypasses the resistors, so it should run on HIGH even if it won't run on low or medium speed. If it does, look to replace the resistor pack.

Are you sure your pins are 5/16"? XJs had 5/16" center pins. My recollection is that MJ factory springs used 3/8".

Alexia's photo shows an XJ proportioning valve. Pete's photo, in the second post in this thread, shows an MJ metering block. Take your pick. Personally, knowing that the purpose of the XJ proportioning valve is to ensure that the rear brakes don't do anything until you hit panic stop pressure, which will then result in the rears locking up before the fronts and the back end of the truck suddenly preceding the front down the road, I think putting an XJ valve into an MJ is a VERY bad idea. But ... I'm an olde pharte, and I prefer to have brakes that work all the time, not just when some dweeb engineer who probably never drove a Jeep or a truck in his life thinks they should work.

Agreed -- cut it off. Although I've had good luck clamping the round head in a pair of Vise-Grips. It helps to clamp the leaves together on both sides of the pin with C-clamps to take the load off the nut.

The difference in the ohm range is insignificant, IMHO. Factory fuel gauges aren't all that accurate, anyway. The real problem is the change in polarity. The '91 and '92 are 105 ohms for empty, where the early years were zero ohms empty and 88 ohms full. Obviously, a mismatch between the sender and the gauge will cause the gauge to read backward (as well as to be slightly [more]inaccurate). One solution would be to go to the hydra plug where all the wires plug onto the gauge cluster. Identity the two wires that are for the fuel gauge. If you can pull those wires out, just do so and reverse them. If you can't remove the push-in connectors, clip the wires and splice to the opposite stubs.

Nope. Same is same. Same is not different.

The HVAC system has a bunch of flappers in the ducts behind/under the dash, and they are all controlled by vacuum. Pay close attention to where each vacuum line runs and what it connects to. I suggest using pieces of masking tape, and marke each side (the tube and the fitting) for each connection with a letter code (A-A, B-B, C-C, etc.) to keep it all straight. While it's open, check the vacuum hoses for cracks and splits. And while the dash is out I strongly recommend replacing the heater core (and a/c coil, if you have a/c). If you don't, WHEN (not if) they fail you'll be removing the dash again to replace it/them.

The early 4-bangers came two ways: Either with a single serpentine belt, or with multiple vee belts. Which type does your engine have? I believe you MUST stick with that, because my understanding is that the vee belt set-up has a water pump that rotates in the "normal" direction, where the serpentine belt set-up has a water pump with "reverse" rotation (same as the 4.0L). CONFIRMED: Just checked the parts manual. The water pump has a different part number depending on whether it has a serpentine belt or does not have a serpentine belt. You can change from one to the other but, in addition to the water pump itself, you'll also be looking at changing the crankshaft pulley, the alternator pulley, the a/c or idler pulley (if you have one), and the fan pulley.

The early ones were 0 to 88 ohms. Going from memory, the later ones were something like 4 or 8 ohms to about 108.

Stock height or lifted? I put '94 YJ hoses on my SWB '88 MJ when it was lifted 4 inches. They were (and are) fine after I put it back to stock height.

That's my understanding. The 3.1 or 3.4 has to be from a rear-wheel drive model.

Oh, yeah. Definitely not worth losing sleep over. I still maintain that zero toe-in is what we strive for. The least rolling resistance and the least tire wear will obviously occur when the tires roll straight when going down the road. So ... why do we set some initial toe-in? Because of the "slop" in the steering components. Each tie rod and has a small bit of slop built into it, and that gets progressively worse as the miles add up. If the front end is aligned with all the tie rod ends at "mid-travel," once you start to drive down the road the rolling resistance of the tires on the pavement will tend to push against the TREs, taking out all that slop. If the setting was zero toe-in at rest, then the result will be toe-OUT under dynamic driving conditions. In the "good old days," the better alignment shops used to put a spring-loaded spreader bar between the front tires when the vehicle was on the alignment rack, to force the fronts of the tires apart and take out all that slop. They could then adjust the toe-in to between zero and 1/16th, and you'd have a top shelf alignment job. I don't have an alignment rack or turntables. I have a gravel driveway. I drive forward into my working position, measure, and make an initial adjustment. Doing so causes the sidewalls to bend while the tread contact patch wants to not move. To allow for that, I back up several car lengths, then pull forward to the same position again, which relieves the sidewall twist and (hopefully) gets the tie rod ends loaded as they would be when driving. Then I check my measurement, and adjust again if I don't have it right. Rinse and repeat as many times as necessary. My goal is zero, but I stop fussin' if I get to about 1/16 toe-IN. Toe-OUT is unacceptable, and I wouldn't be happy with 1/8 or more of toe-in. But ... that's just me, I guess.

What's it work out to with a 31" tire Eagle? I set my toe at 1/8". 9/64

Holy moly! 3-5/8" backspacing, and an 8" rim? You're going to have a LOT of rubbing with that setup. The inner rim/bead is going to be an inch and a half farther outboard than stock rims, and then add another inch of wheel width and suddenly your tires are going to sit two and a half inches farther out than stock. You won't rub the control arms, but I'll almost bet you'll be hitting the flares when you [try to] turn, and the tires will whack the flares when the suspension compresses.

I stand corrected. According to the 2000 XJ service manual, the "preferred" toe-in is 0.25 degrees (they no longer specify it in inches). I got curious and plotted that with my AutoCAD software. To my great surprise, that works out graphically to ... 1/8" for a 29" tire.. All I can say is that my 2001 XJ measured 1/8" toe-in after replacing some tie rod ends, and the steering was rather squirrelly. I set it as close to zero as I could (maybe 1/32 toed in -- you don't want toe-OUT), and things are much better. It's been like that for almost 10,000 miles and the tires are wearing evenly.