Eagle

Not really. I tried to cut them close to the centerline, but I wanted to be far enough off the center that I would screw fittings in and still have them stay there. One of them (I think the MJ unit) was done on a metal-cutting band saw in a friend's machine shop. The other one (probably the XJ unit) was done with a hack saw in a vise. If I can find my box of take-out units, I'll see if I can drop the same size drill bits into both (**IF** I have a spare MJ unit that's intact. I know I have several XJ units.)

Duplicate threads merged.

I don't think there's any difference in orifice/passage size between the XJ and MJ valves/blocks/whatchacallems. XJ: MJ:

Okay -- and now you have no brake system warning light. While I am well aware that anyone with half a brain should know if they've lost the front or rear brakes, I don't think it's legal to remove that feature from a vehicle that's registered and driven on public roads. And it doesn't gain you anything -- the MJ block that you eliminated doesn't have any proportioning function, so it's basically doing the same thing as the tee you installed.

Here's my understanding on the XJ vs. ZJ proportioning valve issue: XJ rear brakes are drums. All modern (since about 1930, I think) drum brakes are what used to be referred to as "servo-assisted" brakes. This was so well-known that they stopped using the term long before drum brakes were phased out in favor of disc brakes, but AMC still used the term in their factory service manuals back in the 1960s. What the term means is that the geometry of the shoes and hold-down hardware is such that when the brakes are applied when the vehicle is rolling forward, the rotation of the drums tends to grab the shoes and rotate them against a cam block or pin of some kind to wedge the shoe tighter against the drum, thereby increasing the braking force with no increase in peddle pressure. This is why with drum brakes the parking brake always holds better when the vehicle is pointing downhill (forward) than when it's facing uphill (when the tendency is to roll backward). The reason for a proportioning valve in a front disc/rear drum setup is to limit the braking to the rear wheels in order to compensate for the fact that disc brakes don't (can't) have any servo-assist function. Some vehicles have more of a problem in this regard than others. I've commented previously that the 1968 - 1970 Javelins were front disc/drum rear and did not have a proportioning valve. The 1968-1970 2-seat AMX, which was the exact same car but a foot shorter, DID use a rear proportioning valve. The reason was that the shorter wheelbase made the AMX easier to spin out if the rear brakes locked prematurely. I don't know of any way to document it, but I have read that the ZJ proportioning valve provides LESS proportioning (i.e. more braking) to the rear wheels than the XJ unit. This is because the ZJ has 4-wheel disc brakes and doesn't have any "servo-assist" at the rear wheels. Staying with the MJ unit is just taking it a step farther by not having ANY proportioning. That said, I assume there is already some "proportioning" built into the system, based on the relative sizes of the front and rear rotors and the size of the pads and caliper pistons. I drove my '88 MJ with rear drums and no proportioning for several years before it took itself off the road. Except for one incident that was a result of a combination of circumstances, it was not a problem. I can't know, but I don't think it would have been any different with disc brakes in the rear. And, of course, if it becomes a problem it's relatively easy to plumb in a Wilwood adjustable proportioning valve and fine tune the system. Related reading assignment for the day: https://www.quora.com/Which-one-is-best-drum-brake-or-disc-brake

10-4 ... 1/2x20

True, but you know what happens to your brakes when a line breaks w/o a proportioning valve. They disappear... :???: No, they don't. Both the XJ/ZJ proportioning valve and the MJ distribution block have completely separate circuits for the front and rear brakes. If a front line or hose breaks, you will still have rear brakes. With the MJ unit, you'll have 100% rear brakes, with the XJ/ZJ unit you'll theoretically have 100% rear brakes but more likely you'll have proportioned rear brakes. If a rear line or hose breaks, you'll have 100% front brakes (which you always have, anyway).

With what size engine? If it was off a 6-cylinder it's probably too big for a 2.5L.

The Carter YFA that I'm familiar with is a computer-controlled carburetor that was used by AMC -- I think it's what they used on the '84 and '85 2.5L engines. If that's what you have -- forget it and buy a real carburetor. If you have an older-non-computer version, it may be okay.

Comanchecrusher has a new thread going, on carburetors, so this thread is closed. Otherwise we'll all be talking in circles.

Do everyone a favor and wait more than two minutes before re-posting the same question. If you need to clarify something you already posted, that's why each post has an option for "EDIT" beneath it. Parallel threads merged ...

How do you know it has to be something with the TPS? I've had symptoms like that in older, carbureted vehicles decades before we had such new-fangled thingies as throttle position sensors. When I was starting out playing with cars, the only throttle position sensor was the driver's right foot. Got any vacuum leaks? How's your fuel filter?

Not much better. The long bed still isn't 8 feet inside, so you still can't put up the tailgate with 4x8 sheets in it. And there still isn't 4 feet clear between the wheel arches, so you still can't lay the panels flat on the floor.

This calculator http://www.gtsparkplugs.com/CarbCFMCalc.htmlcomes out with needing 166 cfm if you want to keep 5,000 RPM as your redline. Summit's on-line calculator https://www.summitracing.com/expertadviceandnews/calcsandtools/cfm-calculatorreports 187 cfm Here's another calculator http://www.csgnetwork.com/cfmcalc.htmlthat reports 166 cfm. So somewhere around 160 to 180 cfm is probably good. Too small will run well at low RPM but you'll be starving for power (which the 2.5L doesn't have an abundance of to begin with. Too big and you hurt fuel mileage. The third calculator I linked to above reports 220 cfm for 100% volumetric efficiency -- which would be a VERY high performance engine, and is basically impossible. So figure around 200 cfm as the maximum you'd want (I think).

I thought you said in your other thread on this topic ( http://comancheclub.com/topic/53258-carbureter/) that you already have a carburetor. :???:

The fuel pump. Carburetors need a maximum of around 7 psi (IIRC). If the pressure is too high, it will blow right past the needle valve and flood the float bowl. I think the best idea would be to scrap the OEM fuel pump and buy an aftermarket pump made for use with a carburetor. You also need to find an appropriately sized carb. The carb used on the 2.5L Jeep engine in the '84 and '85 Cherokees was trash. If I were doing a carb conversion on a 2.5L (something I'm considering, actually), I'd look for a non-computer controlled carburetor. Back in the late 1960s, AMC had a 199 cubic inch version of the in-line 6 (the same basic engine as the 4.0L Jeep engine) that ran on a 1-barrel carb. A 199 c.i.d. is 3.2 liters, which isn't that much bigger, so a carb for that engine might work. I had a Rambler American back then. With the stock 199 engine, an more open air cleaner and a glasspack muffler, I routinely got 28 MPG on the highway.

Unfortunately, that's where the bulk of Jeep's market is these days. "Jeep" has become a commodity vehicle. They aren't interested in building Jeeps any more, they're only interested in selling vehicles.

There's a remote possibility I might be able to stir up some interest in the extended cab version The others (the short 2-door, and the 4-door) are just plain awful. The 4-door needs to get a longer wheel base and rectangular rear doors. There's just NO reason for those stupid doors on a crew-cab pickup.

... does NOT mean you know how to use it. I've been having a shimmy in my late wife's 2000 XJ recently, showing up at about 58 MPH. It's a problem, because I'm currently working a couple of remote construction sites and have to drive 150 to 200 miles each time I go there -- mostly 65 MPH highway. So over the weekend I took off the two front tires and schlepped them back to Wal-Mart, where I bought them, to have them rebalanced. No charge, because I paid for lifetime balance when I bought them. Dropped them off, walked over to McDonald's next door for breakfast, walked back and they were ready. Took them home and installed them on the vehicle. And ... now the shimmy is worse, and it starts at 55 MPH rather than 58 MPH. So ... anyone who is trying to diagnose death wobble and tells us it "can't be tire balance because I just had the tires balanced" ... I've got news for you. Oh, and I'm certain my problem is the tires, because while I was getting the tires balanced I put a set of old, barely legal, el cheapo tires I took off a used Cherokee a couple of years ago. No shimmy with those, so it has to be Wal-Mart's balance job.

Auto Zone http://www.autozone.com/engine/head-bolt-kit/edelbrock-head-bolt-kit/857875_0_0 Oops. Hold on ... just noticed that I searched for '86 Jeep 2.5L, but the fine print says these are for a Ford 429-460.

74 and up

Which line of SMP? They make one line that is "Absolutely the cheapest option that will work long enough for you to sell the vehicle, or maybe to get you to the liquor store and back" and another that is "Not the greatest, but at least it isn't BWD." T-Series is what they call the terrible stuff, and the P/Ns are the same as the better stuff but with a T on the end. IE the automatic TPS is a TH67 for the better one, and a TH67T for the junk one. I didn't know that. Times change -- back in my pony car days, Standard was the go-to brand for points, condensers, caps and rotors.

The Renix system always requires a bit of cranking before the engine starts. That's the nature of the beast. However, once it starts it should stay running. Have you cleaned the IAC (Idle Air Controller) and adjusted the throttle position sensor?

Historically, I've needed mine on average maybe once every four or five years. However, Connecticut is now using that liquid "auto eater" salt solution, and that REALLY eats up brake lines. My 2000 XJ 5-speed came within 50 bucks of being totalled this past winter because a front brake line popped. I'll be replacing with Cunifer line, which is supposed to be more resistant to corrosion. With three XJs and three MJs (not counting the hulks), I expect to be using the flaring tools a lot more over the next few years.

Have you checked the fuse for the TCU?