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About ShortBox88

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    Enduro Racing, Jeeps, Welding
  1. After looking at images of 4.0L engines online I think I've determined that this isn't likely to work out in a bolt on manner. I'm still tempted to head to the salvage yard and fool around with mixing and matching parts to see if something will work out, we'll see if I get motivated tomorrow. Here is a photo of a later WJ/TJ 4.0: You can see that there is a boss cast into the block near the oil pan towards the front of the engine that I believe supports the AC compressor in the later model/post redesign configuration that puts the AC compressor below the PS pump. Also notice that the water pump inlet projects out to the driver's side nearly horizontal (routing the lower rad hose between the PS pump and AC compressor), whereas on the older HO and Renix 4.0 the water pump inlet points downward from horizontal in a way that I suspect that would try to run right through the AC compressor location on the later WJ/TJ location... Hmmm...
  2. I attached instructions on modifying saginaw pumps I downloaded a long time ago from WTOR's site, I hope no one minds me reposting this info. The pump shown in that document is a Saginaw P-pump but the internals are very similar to the TC on the MJ/XJ/ZJ/WJ. I did the 01+ WJ V8 pump swap and the high pressure fitting that comes on the pump has a really large bore, much larger than 3/16" and isn't compatible with the stock high pressure line. If you do use this pump you'll need to use the XJ/MJ TC pump high pressure fitting and you can drill that for more flow, IIRC a 3/16" drill didn't actually remove any material on my original TC high pressure fitting. I opened mine to about 0.200" on the drill size for the high pressure fitting. I think I used a late model XJ high pressure line to fit around the WJ pump reservoir. Here is what the TC piston looks like and what I did to get it apart: There weren't any shims but rather the threaded fitting you see here was glued in place such that some space was left between the threaded fitting and the piston body to mimic a shim. I cleaned off the old glue and then re-installed with some loctite red and screwed the fitting all the way into the piston body to bring the operating pressure up. I'd shy away from adding small machine washers underneath the spring inside the piston to further increase pressure, I believe I blew a P-pump apart that way - twice, although I did also try opening up the high pressure fitting to 5/16" at the same time, so maybe that contributed as well. First time I blew the back of the pump out and after I fixed that, the pump shaft broke on round 2... At least it didn't explode the PS gearbox and had not rolled out of the shop... Maybe I just had a defective or worn out P-pump, it was the original pump on my van with 177K on it at that point... The P-pump is different than the TC so that's another variable... Try closing the gap/removing shims (if present) first before adding shims under the spring in the piston, didn't work for me on the P-pump but maybe the TC is more tolerant? The attached instructions also have you take some off the limiting stud if you do decide to shim the spring inside the piston. The WJ V8 TC pump for the hydraulic fan setup runs a really large hole in the high pressure fitting so my best guess is shimming the spring in the piston is what put my P-pump over the edge. upgrade saginaw pump.pdf
  3. I was curious if anyone had attempted to use 99+ WJ 4.0L drivers side engine accessories (PS pump and AC compressor) + the mounting brackets on the older Renix or HO XJ/MJ engine blocks? I've read a number of threads on various sites where it is stated that these are incompatible because bosses on the block are either missing, not in the right place or not drilled tapped for the newer style accessory brackets (although the context usually seems to be adapting the older HO or Renix accessories to the later model redesigned 4.0 block found in later TJs and WJs 1999 or 2000+? in the case of engine block swaps). In my case the 88 Renix 4.0 still has working AC that I'd like to keep. After briefly poking my head under the hood of a 99 4.0 WJ at the salvage yard last week, it seemed like one possibility for on board air would be to use the WJ brackets and accessories on the drivers side of the engine block and use the 99+ WJ 4.0 AC compressor converted for air compression duty and retain the original AC compressor and alternator on the passenger side of the engine block as they were from the factory in 88. Just wondering if anyone has tried this? If so, what did you find out? Did you need to use the later horseshoe style intake to make the brackets/pulleys/etc. work? What about adapting the later model belt tensioner and belt routing? It'd be great if there was a mostly "bolt on" solution to add a second AC compressor for use as an on board air system. Aside from a tank, compressor and high pressure line I believe I have the rest of the components (drip oiler, filters/separators, pressure switch w/unloader, check valve, etc...) from an engine driven on board air setup that I kept from my old CJ5...
  4. I like this mod, I'll have to dig up the later bottle and pumps to free up engine bay space. With the XJ booster installed and stock air box the original washer bottle did get moved about an inch forward and it just touches the stock airbox and the booster. I had to trim the stock airbox lid slightly to free up space. Yep, that is one thing I did like about the OEM setup, the redundant line for full pressure braking to the rear if you lose the front. However, I've been thinking about whether that would give you better control of the vehicle in a situation where you've lost the front brakes and are rear brake only? Not sure...??? Here is a list of what I did do since my last response on this post (apologies if some of this wanders off track): Found and pulled a 3.73 D30 front housing from an '85 Cherokee and a 3.73 Explorer 8.8 LS disk brake complete rear axle from a '96 Explorer at a local pick and pull. Decided that I will likely sell the XJ D44 3.55 LS rear and matching front D30 axle I originally intended to use. New upper and lower ball joints on the D30. Added a CJ D30 1310 u bolt yoke for the driveshaft connection and new pinion seal to the 3.73 D30 along with new upper control arm bushings. Put my original D30 knuckles, brakes, unit bearings, etc... on the new to me 3.73 D30 front. I had already converted my original CAD dana 30 to a 1-piece axle shaft setup w/297s so re-used those axle shafts in the 3.73 housing. Added new early 90's GM truck flex lines to the calipers and relocated the hard line on the frame on each side to accommodate future lift. On the 8.8 had to put in new parking brake parts (they were shot) and wheel seals on each side. Calipers, rotors and brake pads all looked to be in good shape so I used them. Used 2 long side (passenger) Explorer parking brake cables, one is a little sticky so it may get replaced next time I head to the u-pull. I also pulled some extra steels and friction plates from another LS 8.8 to help the original LS clutch packs that were pretty beat. Grabbed a 1310 companion flange from a 2WD Ford Ranger with an 8.8 rear to mate up to the stock driveshaft. Cut the spring perches off and moved them out to match the MJ leaf spring spacing, set the pinion angle under the truck and welded them on. Added a new 96 Dodge Dakota rear brake flex line to accommodate future lift. Had to replace the hard lines on the axle as I used a second 8.8 passenger side flex line to the caliper on the drivers side caliper. The original 8.8 drivers side flex line to the caliper is integrated into the tee fitting and flex line that goes up to the frame, I didn't want to re-use this so the Dakota flex line was put in it's place and a short hard line was installed to run to the drivers side caliper + the second passenger side flex line installed on that side. Put on some slightly taller XJ lift shackles that I had pulled from the same 96 XJ I got the booster/prop valve/MC from. All in all with the stock springs, slightly taller shackles and SUA with the larger 8.8 axle tubes I lost about 3/16" height in the rear... Note - the stock driveshaft is too long, I knew it was tight but I decided to test drive it anyway - pushed the rear output bearing into the transfer case and broke out the shoulder the bearing rests against out of the tailhousing. The bearing was still in the bore where it should be, but just pushed in enough to break the shoulder. I've been having aluminum in t-case oil issue for a while now and after the test drive I had planned to swap the oil pump and clean out the t-case thinking that maybe my oil pump was the issue, I've looked almost everything else and can't seem to figure out where the aluminum is coming from... It's not the chain, clearanced the alum shift fork where it was showing some wear, etc... As I took the case apart I found the break in the tail housing... If I had not been planning a pump replacement I may have never know that the damage had occurred. At this point I'm over it and done with this t-case, it's been apart too many times and I'm tired of trying to sort it out - so I'm just trying to get it to function a while longer. I know it's kind of a BS fix but I have a Strongbox/EB Dana 20 that I'm waiting on a few parts to finish, plus a lift going in soon so I decided to make it work with the driveshaft I have for the time being, so the slip yoke on the driveshaft got trimmed about 1/2" and the bearing was re-installed with some bearing and sleeve retainer using the extension housing to place the bearing... The lift is the next step, so at that time I *may* decide to replace the driveshaft slip yoke and t-case tailhousing until I get the Dana 20 finished and some driveshafts built to fit the lift and t-case transplant correctly. I just didn't feel like spending the money to get the driveshaft shortened only to replace it entirely in a few months... Seems to be working right now, I guess the only way I'd really know is to drive it some more and pull the case apart again to see if the rear bearing moved in the tailhousing (not likely unless I have to). Or the bearing will just walk into the speedo drive gear and the case will start making nasty noises... I thought it was worth mentioning that the stock driveshaft was too long on an 8.8 swap at stock height/springs (mine is a Pioneer with the D35). Not sure if this would be true for all short box MJ's with Dana 35s or not... Another way around it would have been to use aftermarket spring plates that let you move the rear axle back or possibly a junkyard rear driveshaft form a Dana44 manual or Dana35 automatic shortbox MJ from what I read, but I was re-using the 8.8 perches and my existing driveshaft for now for now. I removed the LSV and simplified things down to a single line to the rear brakes. I considered keeping the redundant emergency line but rounded off the brake line fitting when trying to get it apart, I think it had pretty much rusted itself to the line... decided to just remove it... I re-bent and re-flared the primary hard line from the dist block to mate up with the Dakota flex line at the frame side. I had cut the Explorer frame side mounting flange off with the original flex line on the 8.8 so I trimmed and welded the Explorer frame side flex mounting flange to the MJ frame side flex mounting flange and the Dakota flex line went right into the modified Explorer/MJ flex line frame side mounting flange with a little filing on the flange. Put in the 96 XJ booster, MC and prop valve - however, I pulled disk brake ZJ prop valve guts and swapped those into the XJ prop valve/distribution block to get hopefully better performance out of the new to me rear disks. Interestingly, the XJ booster, MC and prop valve/dist block I pulled were from an ABS truck. I want to say that side by side with the MJ distribution block the orifices in each of the brake line ports visually appeared to be identical in size, I was in a hurry having borrowed shop space to do the swap and didn't measure the diameters in the brake line ports, but it was definitely smaller than the ID of the 3/16" brake line. From the pictures above what I assume is a non-ABS XJ dist block clearly has larger ports. That and there is only one feed for the front brake lines on the ABS XJ distribution block, which goes to the ABS unit that then splits them to each side. Where you would normally have a second port for the front brake lines, labelled RF below the ABS XJ dist block had a plug. I replaced this plug with the RF fitting from the MJ dist block to get two ports on the ABS XJ dist block Just a note - not my picture, just using it in this post to illustrate... So probably not the best way to do it but the brakes DO work better than the original setup. I question whether my rear drums on the 35 were working at all... I still have to stand on it a bit to get wheels to lock up with 30" tires. I did bleed the system pretty thoroughly. I would have liked to have taken the swap a little more slowly but was borrowing shop space and had limited time to tinker with the brake setup, so worked with what I had. I'll likely have another opportunity to mess with the brake system in the next couple of months so I may either track down a non-ABS XJ dist block to swap in or maybe do something like what coolwind57 did above with and adjustable prop valve and maybe improve this further. Here is what Wilwood said about the single inlet/single outlet adjustable prop valve they sell: " Hi Mark, Thank you for the inquiry with Wilwood Disc Brakes. In general, the output pressure/input pressure ratio will remain consistent. I.e. if you have the valve adjusted all the way and input 1000 PSI, it will output 430 PSI (max 57% pressure reduction). Now, we don’t recommend exceeding the PSI limit of the valve as it may not regulate pressure correctly beyond that point. Regards, Wilwood Disc Brakes " So it just provides a constant pressure reduction such that you get a % of the input pressure coming out of the valve, I'll have to check out the speedway unit, I'm guessing it likely does the same thing but did not think to ask about if there is any pressure reduction when the valve is fully open. Thanks everybody for contributing the knowledge and experience with the braking systems. It helped me quite a bit!
  5. I don't see why that wouldn't work. Would you also need to drill out the hex fitting labeled RF line in this picture as well? (I know it's not an MJ valve, but same arrangement on the MJ valve, I think)
  6. So, if I'm following, you ran a single hard line from the front brake feed on the MC to a convenient point to transition to a flex line down to the front axle where you have a Tee installed and hardline to each side of the axle (somewhere around the inner C on each side) then a flex line to each caliper? Kind of like older Dodge pickups? Or did you keep hard line to each "frame rail" up front at the stock location and put the Tee near the MC and then individual flex lines to the caliper from the frame? Seems like you're giving up the brake warning light and the ability of the stock distribution block to isolate the front or rear brake circuit if either one should develop a leak or fail in a panic stop situation, correct? For the rear brake circuit, I'm likely to do the same as you did, I just want to confirm exactly how the Wilwood or similar single in/single outlet adjustable proportioning valve works first. That is essentially what I did with my van, but I'm wondering if the adjustable prop valve simply holds a constant pressure once you hit the manually adjusted limit and never exceeds that pressure no matter what the input pressure is or if the outlet pressure will still increase (providing the input pressure continues to increase) but at a lesser rate? I sent Summit a tech question on this, usually they are pretty good about getting back on that kind of stuff. May not hurt to contact Wilwood directly either... So maybe the ticket is keep the XJ prop valve I have and swap the ZJ rear valving in when I do convert to rear disks, or just gut the XJ rear valving and use the adjustable in-line prop valve, Cruiser - do you have an opinion on which performs better? I also just noticed something in this thread, while re-reading it: https://comancheclub.com/topic/53274-mj-load-sensing-valve-delete-procedure/?page=4 "For your 92MJ, the 95/96 booster master is pure bolt-in. The only fab you have to do are the two brake lines from your existing distribution block to the new master cylinder. Buy a 2' length for pre-flared 3/16" brake line from AZ or similar, use the two existing flares on the distribution block, bend and flare the other ends for the master, and bolt it in. Easy-peasy and an excellent brake upgrade. " Clearly that's not the stock washer bottle, while looking under the hood today - to get that XJ booster to fit what am I into? I still have the stock bottle and airbox. Looks like it may be tight...
  7. Very interesting, neither the XJ or MJ distribution blocks use a metering valve on the front brake circuit. When I converted my van to rear disks I had to gut the metering valve on the front brake circuit as it was no longer necessary - no need to delay the application of the front disk brakes so the rear drums could catch up since I got rid of the rear drums. I also had to gut the rear brake circuit proportioning valve in the van's distribution block, I assumed it was not really appropriate for the rear disks and I used an in-line Wilwood "proportioning" valve for the rear circuit instead. Eagle - thanks for digging up that picture. In concept, I like the idea of the load sensing valve with the redundant emergency bypass, but I'm not sure I'm a fan of how it is implemented on the MJ. Seems like it would be pretty easy to damage it while off road. I'm going to keep digging on what exactly the Wilwood single in/single out "proportioning" valve actually does as I'm now wondering if that was the right move on my van after reading what 1stDeuce stated about the function of that valve (quoted above in my original post). I did grab a dual diaphragm booster, MC and distribution block from a '96 XJ today, but at the moment looks like replacing the water heater (just found it leaking) is my next time-sink task.
  8. Just so I'm clear on what happened with your Jeep - when you say the metering valve in your XJ was BS, does the XJ combination/proportioning valve include a metering valve for the front brake circuit (I don't know because I haven't had one apart)? Maybe I'll take a look at one when I head to the junkyard today. Or are you referring to the rear brake proportioning valve that is part of the XJ distribution block? Maybe a better way to ask it is did you modify/remove the valving for the rear brake circuit in the XJ or valving associated with the front brake circuit? The reason I ask is a metering valve and a proportioning valve do different things altogether and one is intended for the front brake circuit (metering valve, for front disk/rear drum applications - you would leave out the metering valve if you have all wheel disks) and one is intended for a rear brake circuit (proportioning valve). I appreciate the comments about adapting your driving style to the vehicle you have, my first 4 vehicles did not have ABS and I learned to drive them just fine in snow/ice, etc... My last and my current vehicle did/do have ABS, and if the system is working properly, those systems work rather well. My Comanche does not have ABS and I'm fine with that, modulating the pedal is coming back to me (ABS can make you lazy). But let's not get distracted on the topic of ABS or driving technique. I am interested in learning if there is a combination/prop valve design out there that may prevent premature locking of the rear brakes for the Comanche, so my questions above regarding what appears to be the absence of a metering valve for the front brake circuit on the Comanche specific distribution block and questions about how the Wilwood single in/single out style proportioning valve operates still stand. And yes, I do have new e-brake cables going in as part of the axle swap/lift and I'll be making sure the adjusters and wheel cylinders on the new to me rear axle are good to go. I suppose that doing a rear disk swap at the same time isn't out of the question and may simplify the braking setup. I have an XJ44 rear that's going into it, I managed to get one cheap at a local pick and pull. In any case I'm hoping to grab a 95/96 dual diaphragm booster and MC today, and from what I've read - that should help overall performance of the brakes.
  9. I always use a thin layer of RTV on each side of the gasket. I've been told that the blue RTV is best for contact with water, but not sure if there's any truth to that. Never had issues other than when I use too much of it and make a mess and cause the gasket to move around when tightening the bolts, etc... I seem to remember that at least one of the bolt holes tapped in the head for the thermostat housing is not a blind hole (so threaded all the way through into the head water jacket) so I would also recommend using a copper washer (like for a brakeline banjo bolt) on that bolt or use a thread sealer on the bolt threads - like permatex high temp thread sealant: https://www.permatex.com/products/thread-compounds/thread-sealants/permatex-high-temperature-thread-sealant/
  10. Hello All, So I'm new here but have been lurking and finding good info here since I picked up my first Comanche in Aug 2017, finally got round to creating a profile... I have some questions about the Comanche braking system, I've been reading posts on this forum on this topic as I'm getting ready to lift and axle swap to make sure I'm covering my bases and this one got my attention: https://comancheclub.com/topic/40762-mj-brake-proportioning-valve/ There is a good picture of the MJ distribution block cut in half in the linked thread: My question is why is there no metering valve associated with the front brake circuit? Am I missing something? Is it separate from the distribution block on each front brake line? For a Disk/Drum braking systems I was under the impression that it was important to have a metering valve on the front brake circuit so that the line pressure to the front is delayed such that the rear drums have a chance to apply first since the drum shoes are not in contact with the drum, whereas, the front caliper pads are in contact with the front disk and apply almost instantly when the brake pedal is actuated. A couple YouTubes on this: https://www.youtube.com/watch?v=qzUk8W1-2pw https://www.youtube.com/watch?v=tUEsxZGuMk4 My second question is related to a statement that 1stDeuce made regarding Wilwood adjustable pressure regulators: "The Wilwood adjustable pressure regulator that has only one inlet and outlet is often referred to as a prop valve, but it is NOT. It only functions to limit pressure to an adjustable set point, meaning it'll allow full pressure up to a certain point, then limit it to that pressure no matter how high input pressure goes." I have not been able to find information to support this just doing random Google searches today - Anyone have some insight on what the pressure curve actually looks like for a single inlet/single outlet style aftermarket proportioning valve such as the Wilwood? I was considering using one of these aftermarket proportioning valves along with the LSV delete procedure outlined in the link below to clean up the braking system a bit and have the valving in place for a rear disk swap later on (which would then likely negate the need {or maybe just my perceived need} for a metering valve on the front brake system): https://comancheclub.com/topic/53274-mj-load-sensing-valve-delete-procedure/ However, if the Wilwood single in/out "proportioning valve" is really a pressure regulator that allows full pressure up to a setpoint then flatlines the pressure regardless of the input pressure after that, seems like you'd be leaving some stopping power under-utilized as opposed to a proportioning valve that just affects the slope of the pressure rise curve after the "knee point" or adjustable setpoint. In the interim, my thought is to maybe try using a combination valve off an 80's K-series pickup as I believe I can find one that will have the rear proportioning valve, front metering valve and brake light switch all in one unit and swap that into the Comanche while it is in the disk/drum version and then keep the Comanche distribution block to be used later with the disk/disk, adjustable proportioning valve scenario when I get that project lined up. Thoughts? Also, 1stDeuce suggested a Jegs part as an alternative to a Wilwood proportioning valve: http://www.jegs.com/i/JEGS+Performance+Products/555/63025/10002/-1 However, I didn't see any description of a metering valve being part of that assembly so maybe a good option for a disk/disk setup but maybe not a disk/drum setup due to the lack of the metering valve??? That's all for my first post. Any help would be appreciated.
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