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  1. Its been 3 weeks and i thought i would update this thread with some seat time feedback. I have to say im a lot happier with my brakes and they seem to have burned in a bit more and gotten even better. The one caveat if it is one is that under panic stop hard braking there is a bit of spring in the pedal, i suspect this is the firewall flexing a bit were the booster mounts, stands to reason really this has to be the strongest part of the firewall. One thing i dont have to do anymore is hang back in traffic all the time, i was leaving extra stopping space because my brakes were so shitty were now i can do the 2 second rule at any speed, just like a normal car. I have to say i have to highly recommend this swap, although not a strait up bolt in, with the right tools quite doable and worth doing GB
  2. Mechanically your all in, solid oil pressure, small temp variations look normal. if your header tube temps are fairly consistent you can assume its fueling correctly. thermostat opens fully when she's good and warm. An engine is more efficient thermally when its run at 195. So now you break er in a bit a keep your ears tuned to every nuance of how this thing is running. Third times the charm!
  3. It does, i would estimate around 15%. I can screech my front tires now on a hard stop were before i couldn't, pedal response is faster too. I will admit my method of engineering was, lets try it and see if it works after reading somewhat conclusive information on the net. I fully realized that the CJ and YJ have significant design differences in there booster setups. The brake pedal after all is nothing more than a second class lever and as it happens the CJ has two 2nd class levers with the other one between the brake pedal and the booster. So we have a double underdrive situation multiplying mechanical effect to the back of the booster. My thought was the engineers at Jeep eliminated that on the YJ and must have made an improvement somewhere or they wouldn't have done it. All i can conclude is the booster must be a better (dare i say way better) design, its dimensions are slightly bigger with a lot more volume on the vacuum side and the valving is way more responsive, these changes although subtle seem to be very effective. I seriously doubt it, the Yj is an improvement but i think Jeep finally went to the double diaphragm in 95 because they wanted to (or had to) go from half decent to pretty good.
  4. Thanks Moses for the added info on my swap, the devil is in the details as they say. 60Bubba uses the 8" DD booster / MC kit that is readily available on Ebay. From my research that engineered kit is the final word (the bomb) next to a hydro setup. It should be mentioned as well that OEM grade (organic) brake pads and shoes are marginal at best and metallic or carbon metallic are mandatory. All things considered the booster swap and premium pads (once they are burned in) made my CJ a much safer ride. This is an improvement but for those wanting more or running bigger than 33" tires the DD set up is the way to go. The photos i uploaded are out of order, the push pin from the YJ booster is shown first in its modified (shortened) form. The push pin is threaded inside (1/4-24) halfway down, when i cut it shorter with a hacksaw i ran a bottoming tap down to make some more thread, i then screwed in the hardened ball end. The push pin is semi floating semi self aligning in the front of the booster, the push pin locates in a cup with a rubber floor inside the booster and can accommodate a small amount of misalignment, lets say manufacturing tolerance. My plan is a new MC with the mounting holes more precisely slotted and a cleaner cut on the bottom casting. The brake pedal push rod could be a bit longer and some folks may like the brake pedal a bit further back but i like it were it is. Looking at the pictures the YJ master would have just cleared the rad support rod so the only real issue would have been the lines on the carb side.
  5. Your worrying to much about ordering the wrong part. you have more than enough info to order parts for your tracker. Amazon is a redistributor, a middle man, a very good one granted but they do not have expertise as to what they are selling so the more checks they make the better the chance they will sell you the right part. Try and hook in with a car part house like rockauto. rockauto is the amazon of car parts
  6. The picture to me looks like one side of the rack (as in rack and pinion steering) if you look further you will find the pump mounted near the belt drive on the engine. The rack can be rebuilt and some guys do it but most just re & re it. You've got a end seal going and to replace it the rack has to come out and be dismantled. Some racks are easier than others, to replace the seals you need to remove the tie rod ends as well and if the threads are rusty it will be hard work. Your best bet if you cant get a rack right away is try a seal sweller, its an additive that you add to the p.s. fluid and it swells the seals, this will slow or stop the leak for a while. a heavier hydraulic oil might slow it down a bit too. try to steer only when the car is moving as that will keep the temp of the fluid down and less will leak out also the system works hardest when you are maneuvering into a parking spot for example. Maybe you can order a rack from Rockauto they ship everywhere.
  7. Well i did the swap, the pedal requires less effort and braking is improved, i retained my master cylinder which required slotting the mounting holes and cutting the casting at the bottom. The drive rod behind the master needs to be swapped or modded. Using the taller YJ master would have hit the rad support rod and put the lines on the carb side. Link rod inside simply hooks up and the brake pedal and is maybe a we bit lower.
  8. Looking for info on this swap... I have a air leak in my 83 CJ power brake booster, i need a new or reman booster of course but im thinking take the opportunity to upgrade (if it is one). Anybody done this YJ to CJ booster swap or have good info please share. thanks
  9. I hate to say it but think this is a classic lobe has gone flat on the cam symptoms....well in my experience anyway. When they start to pop out of the carb like that its ``Ùgh time to change the cam`` If you fashion a piece cardboard to act as a push-rod oil deflector you can briefly run the engine with without the valve cover and not make too big a mess. Look for the rocker that's not moving or hardly moving, that's your bad lobe. Did you notice the problem after going for a long drive, you got home and it wasn't running quite right, an then it got progressively worse? My guess is its an exhaust lobe, the popping back is non exhausted air blowing back past the intake valve at the start of the valve opening cycle, its worse when you give it throttle as you're feeding it more air to back pump.
  10. Retinking my last post, trying to nail down a lean cylinder under load is pretty tricky, you've got exhaust temp and reading the plugs to go by. reading exhaust temp you'd have to rig up a pyrometer and move from pipe to pipe, mount the gauge on the hood, bomb down the same stretch of road at the same speed, you get my drift (: not the most practical. Im thinking a lean injector may not show up idling or revved up in the driveway but if you have a cooler pipe at idle that could be an indication. If you unplug (electrically) each injector and see if number 1 makes little difference that could be an indicator. I had a TPI once were i had a couple cooler cylinders and i traced it to bad connections at the injector, one as i recall, i had to solder a new connector on it was so bad. The ECU generally by design are pretty bullet prof, but they do go bad, had em where the motor starting and running had issues and swapping out the ecu fixed it.....or at least made it better so other issues could be found too.
  11. Everything you describe about the oiling system and clearanses says solid build, good to go. The Melling pump spec`s perfect regardless of sketchy gauge. This is starting ta point big time to running lean on that first hole, that burnt spot on the back side of the piston is evidence, this piston is soaking up so much heat oil can't cling to it. Get out your non contact thermal temp gun and compare temps across your cylinders shootin the header tubes close to the port, try different rpms, open and closed loop, hot and cold, the injector or the wire to it, something has to be amiss. If number 1 tube is hotter than the rest, that's lean. Try swapping that injector to another cylinder. or if you have a set from another motor swap em all out. is that intake runner loose at the head, is air getting in somewhere to make that hole go lean? Is number 1 injector at the end of the line on the fuel rail, do you enough fuel pressure?
  12. My understanding (what ive read around the net) is 88-90 blocks are cast similar to 4.0, my block for people who what to keep an eye out for one can easily be spotted as it has 5 freeze plugs like a 4.0 not 3 as with pre 88 4.2s. My understanding, which as i keep investigating is probably wrong was that the 4.0 and 4.2 have the same compression height, the difference in stroke is made up by the rod. I was hoping the 242/258 were similar to the Chev 350/400 in that the engines used the same compression height but just shortened the rod to accommodate stroke change. What ive read lately about the 258/242 is they changed deck height in different years so that complicates things more. The Chevy is easy compared to this motor as there is a ton of info where the AMC is bits and pieces here and there not always correct. I think im gonna do the 1990 258 head swap and the 4.6 stroker as a more long term thing, swapping the motors out later could be done over a weekend. For the intake im using the 2000-up efi intake and im going to weld or epoxy a 2 barrel carb adaptor to it. iLL know more about the 242/258 parts interchange when i pull the motors apart and start measuring parts.
  13. Im looking at building a motor for my 83 Cj7 I have options, I have a 96 4.0 parts motor with 0630 head plus a spare 7180 head. I have two 258s one is a 1990 (006CL25 / EF3235444) the other an 80 (009C09 / 3235444). The 1990 258 i could just re-ring and drop a 4.0 head on, i wouldn't even have to plug the water jacket holes in the head as the 90 block is squared of on that side like a 4.0 block, re cam with a RV unit and i'm hauling like never before. Pretty strait forward. Or; Take the crank and rods from the 1980 block and put them in the 4.0 block. With this one i would keep the 4.0 pistons, install new rings and because the 1980 crank is the last of the 8 counter weight heavy cranks i would assemble it and assume im pretty close on balance and see what it runs like. Im thinking the second one is a bit of a gamble on the balancing but i've put lighter pistons in small block chevs before and never had to rebalance, so ive been there done that. Anybody out there done a heavy crank to 4.0 swap with all stock stuff? think it could work?
  14. I think you pulling number one piston and rod assembly twice and having a stiff piston on pin situation both times is an indication of a problem right there. On top of that you have scuffing in that same bore as well. Scuffing is a form of micro welding that occurs with friction (heat) between two metal components in the absence of lubrication. On a jeep six the oil pump is in the middle putting cylinders 1 and 6 furthest away, for some reason number one is not getting enough oil, question is why? First up, what is the oil pressure when the engine is hot and at cruising rpm? if its 10-15 psi we've got a problem. Get a proper mechanical gauge mounted to monitor the pump pressure. Second is there a restriction at number 1 is there a issue with the main bearing oil hole and upper bearing shell alignment. is the clearance on this bearing excessive? Third maybe a bad cam bearing at that end dumping oil that should be going to the # 1 main.
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