Doing a Ax15,and YJ Booster Swap

[ThisGuyUKnow]

More pics of the Driveshafts installed. Still looking for a new hydraulic clutch linkage. I have a line on a guy locally that I am going to check out tomorrow but I am looking at dropping 150 on stealership only available part.

 

[ThisGuyUKnow]

I picked up the hose that runs from MC to the SC from Local Cj guy (I mean CJ guy, he had 1 white CJ Laredo, 1 Cj 6, 1 CJ8, another CJ7 with the front clip removed, a CJ8 tub 3 cj tubs, 2 YJ tubs, axles galore, D300s everywhere, pretty much every tranny ran in a cj ever all laying around) Mopar says you aren't supposed to be able to replace just the hydraulic line, but they also tried to make it so you couldn't bleed the linkages as well, but the thing had to of been put together somehow in the factory, the companents didn't just go in a cauldron and magically fuse together. SO I am going to try to cheat mopar tonight and see if I can't get it all in.

I finished the floor panels today. I couldn't find any decent rubber gasket material so I went to the store and picked up some little kids arm floaties and decided to make do.Its not pretty but the carpet will be going over it and I think it will keep 90 % of the elements out. As far as the floor panel goes I am done. Just got to put the carpet down and then screw in the boots whenever the T-5 boot I ordered gets here.

Once I get the clutch working and away from the Exhaust all I got to do is take it to my mechanic and have him tune the carb and get the timing right(I tried and failed miserably) and I should be on the road!

Shifters after having the local 4wd shop rebend them. they charged me 20 bucks a shifter! I think that is a little steep but we didn't discuss price when I dropped it off so thats on me.

My Make shift weather gasket

First Attempt/Failure at making a plate/gasket for the access plate I made so that the shifters can be easily removed. With my clocking part of the shifter's arm is poking through the floor so i had to make room for its throw.


My revised access plate.

Installed

Tranny Access Plate in

 

[CJ]

You have done an excellent job of documenting your trans change and we really appreciate it! Great job!

 

[ThisGuyUKnow]

You have done an excellent job of documenting your trans change and we really appreciate it! Great job!

Thanks i just did a lot of research and no one really documented it in complete detail so I just posted up what I would have liked to have seen when I was first researching this swap. I think what most people should know this is not as cheap as you think. I thought man I can get a new Ax15 for 200 bucks and put it in and new drive shafts ladeeda. Well you have to get a Hydraulic clutch which new is 165 and sometimes they come with the tranny sometimes not, then there is the flywheel, clutch, AA clocking ring and Input housing(I still think that you might be able to resell the clocking ring and just use the new input housing and redrill the tail housing to match the stock clocking), the list goes on. Its definitely making me consider future swaps I have planned as the cascading affect down the rest of the vehicle really surprised me and caught me compeletely off guard.

On top of that I am honestly a little fed up with it. That hose turned out to not fit the master cylinder so now the truck is in-operable still and the clutch hose melting on the pipe was just a stupid issue to have. On top of that while I was putting the carpet and painting the top today I had the radio on and after a while I went to crank up the cj to charge the battery and now it is back to not idling at all which is a problem I thought I ran down a week ago by rebuilding the carb, replacing the fuel pump and filter. I am hoping that maybe some crud was still in my fuel lines and I just have a clogged fuel filter. If not I may just go back to FSJs and sell this one.

 

[ThisGuyUKnow]

Solved the burnt clutch hose problem cutting it with a pipe cutter and adding a fitting rated for a high PSI from lowes in the line. It worked and seems to be holding.

I went to a pick-n-pull and found a donor cherokee with the hydraulic linkages I needed. I said to myself "hooray now I can replace that cut line with a solid one and keep the cut one as a back up". Well after about an hour in a musty old junkyard car, drenched in my own sweat from the humidity, the final bolt holding the master in stripped on me. Defeat! Well I decided my dream of having a backup master cylinder were shot so I decided to just remove the hose and call it a day.. As I started pulling the hose out you will never guess what I found, The line had been cut and a fitting similiar to the one my dad and I did was holding it together. So I angrily beat on the cherokee for a minute with some of my tools and trudged off having wasted an hour of my life and a whole bunch of calories that I can never get back!

All that being said I finally got the Timing correct on the Cj. My problem was that the timing marks are -4,-2,0,+2,+4,+6 etc.... Well when I "set" my hei to 8 deg BTDC I had actuall set it to 4 BTDC. This dramatically changed everything. The truck isn't dieseling and will idle on its own.

A mechanic looked at it today and sprayed carb cleaner on the intake and told me I have a few leaks in where the intake meets the block as the RPMS jump whenever you spray the carb cleaner where the intake meets the head. I figure since I already know my Exhaust manifold is warped that now I am just going to go ahead and go straight into the next project, 4.0 head, 4.0 exhaust header, 258 intake/carb, Which then will inevitably lead into my next project :4.0 Injection It never FREAKING ends!!!!!! I figure once I get the 4.0 head on and the exhaust header and the new gasket everything should just seal up nice maybe.....

Anyway it is still running a little crumby when you first start it but once you drive a few miles it starts to smooth out.... I think that the gas went bad or got crud in it during the 2 almost 3 months the truck just sat. It had a 1/4 of a tank left of the gas that was in it prior to the T-5 commiting harry carry and I filled it up with new gas. I think I am going to add some octane booster and see if that helps any.

Also I should note that if you are doing this and following what I did do not, what so ever, mount your MC in the same position I did. It needs to go in that little slot that is already punched for the 4 banger cjs behind the brake booster. The current location does not give enought leverage to make engaging in 1st gear smooth. THe other gears are alright but first and reverse take alot of physical effort. To correctly place it I am told you will need to get a YJ clutch pedal and that should just mount with no mods in place of your cj clutch.( so i am told) It does work were it is currently but there is a better way to do it so if you mimic me you are forewarned.

 

[ThisGuyUKnow]

Oh an another thing I almost forgot that is real important.......

When we took apart the master/slave/hydraulic linkage set up to try that new linkage I was given out, we must have damaged the seal inside the slave or something because once we patched the burned section and reatteched everything the slave started leaking bad from where it meets the line. What I did was I took the slave from my NV3550 setup I have waiting to go in my wagoneer and attached it to the line(the nv3550 master is so different from the 94 ax15 set up I couldnt use it). This wouldn't be important except that I had been gearing up to put an NV3550 in my wagoneer and so I had (all from the exact same 2004 TJ) the flywheel, master/slave, and nv3550. When the T5 wen out I couldn't source a new flywheel so I took the one from the 3550 and installed it in the cj(now I need to find another ffor the waggy but the 727 still works so no hurry) .

This is all relevant because originally I was using a nv3550 flywheel from a 2004 4.0 and an ax15 slave from a 1994 4.0. The engagement of the clutch changed dramatically. It worked before with the old slave but when I put in the matched slave the engagement felt and was way better.

The moral of the story is make sure you match your slave (at the least) with your Flywheel. I looked into it and apparently Hydraulic linkages are very specific and touchy about throw distances and I ignored it at at first but from experience I can say heed the warning.

Long winded but important

 

[ThisGuyUKnow]

While I have been waiting to get my head back and get my 4.0 injection parts, I have been outing alot of research into the clutch pedal assembly. What I have discovered is that you can just release the c-clip on the original clutch pedal and pull it off and replace it with a yj pedal and done just drill the hole for the mc and everything should hook up and function correctly.

Since I have to pull the mc off to drill he mc slot, I am going to go a step further and swap in a whole yj brake/clutch assembly. The advantage to this extra work is that by doing this I can swap in a yj brake booster instead of reinstalling my original one. This means that I will not have to lengthen the rod like most people have to do. Basically instead of having to fab a design by Tim, I will be running all compenents that were designed by the engineers at Jeep to work together from the factory and I feel this will for one make it look nicer and two eliminate alot of potential for failure down the road.

 

[ThisGuyUKnow]

YJ Brake Booster

Ok I am am back in town and have the the 1995 YJ brake/clutch assembly. The cool thing is that the brackets are almost Identical in the way they mount to the firewall around the brake booster and then on the front on the steering wheel. The clutch pedal also has an extra bracket attached to it that will rest against the fire wall and provide alot more support for the Clutch MC. Ther is also an extra support rod that will have to be drilled into the Firewall on the opposite side of the fuse panel.

A problem I forsee is that I am using a cherokee clutch MC and the MC bracket for the YJ is wider than the one for the XJ.I may just delete the bracket unless I can source a YJ CLutch MC for a reasonable price. Like I said I am trying to make this as "stock" as possible in look and function so sourcing the correct MC would be preferable.

I haven't picked up the Yj booster yet. I am supposed to get one for free from a buddy but if he falls through there is one sitting in the boneyard that isnt as pretty.The booster has the same bolt pattern as the cj one so no mods will be necessary to the fire wall. there is a difference in the hard lines though, the yj's are on the opposite side and the proportioning valve is mounted in a different place. I am going to try to bend my cj lines to the opposite side and if i mess them up or break them then I will probably pull the lines from the aformentioned yj in the boneyard.

I am currently doing two projects at once (the other is fuel injection because i have yet to get the carb to run since I did the ax 15 swap) so I didnt get a chance to snap pics of everything before dark... Will upload em in the morning.

 

[ThisGuyUKnow]

Tranny Access Plate in

I have decided I am unhappy with the extra acess plate on the right I made to clear the body of the front axle's shifter. I want to pull the carpet again and instead of using rubber to seal the area around the trow I want to weld a raised plate. I am paranoid that the way it is the rubber arm floaty is going to give up the ghost and I am going to have the elements funneling through the hole.

 

[ThisGuyUKnow]

Brake booster out


new pedal assembly(1995 yj)

 

[ThisGuyUKnow]

I removed the old pedal assembly today. It was kinda inconvenient but not too terribly bad. the Pedal assemblies are virtually identical except for that brace for the Clutch MC and that extra support rod. I am sure the rod is not necessary and I am sure that the MC braket can be retrofitted to the original CJ braket if you want to get in there and pull the retaining pin. I have to pull the dash to do my blower motor swap and I have the YJ brackets so might as well do it right.

I am going to go pick up the new booster tomorrow so I predict I will be project complete tomorrow evening

Side by side

 

[ThisGuyUKnow]

I put the Yj assembly in today in between remove engine parts for the MPFI swap.

If you do a booster swap make sure that you basically take the booster and mc in your hands and push the rod against the ground. the one I had sat for a long time and was frozen up. Everything went in smoothly. Since I am using all wrangler parts the booster is essentially plug in play there any how. I did foget to drill my new hole for relocating my CLutch MC, which was kinda the thing that prompted the booster swap in the first place. So tomorrow I got to pull the booster back off and punch that out.

I am also going to instal that extra rod support just for grins and giggles. I measures a buddies YJ tub and it is directly in line with the top bolts of the brake booster and about 7 7/8 inches from the right bolt.

My next challenge is finding the correct fitting to make the cj brake lines match the YJ mc. There is a link that BrockGrimes has linked on here that has part numbers for these adapters but I called 2 autostores and they just scratched their head so I may have to figure it out on my own.

It wouldn't be me if I didnt color match the pedals like I did the shift levers

Boosterness

Dash hangin out.

 

[ThisGuyUKnow]

I picked up the fittings to adapt the CJ7 hardlines to a YJ they are Weather Head part #s 7917, and 7912. Your best bet is to either go physically to carquest or Napa. These are napa part numbers but carquest seemed to be the only shop near me that could cross reference the parts. The nearest NAPA to me is like an hour so I just called and gave them the part number and asked if he could give me the sizes from it so I could match it at the zone. Either the guy was an a-s-s or just an idiot but he gave me entirely wrong measurements so my first trip to Oreilly's yeilded 12 dollars worth of incorrect fittings so I had to go back into town and this time went a few extra miles to the carquest with whom I have had good results in the past. So go in person because sometimes the autostore guys can make your life harder than necessary.

I grabbed a tube bender to rebend the lines to the opposite side, but to be honest it was two big to manuever very expertly so I ended up just bending then by hand. I just made sure I got some clearence from all the surrounding objects and everything screwed together.

Now I am not experienced with bleeding the lines but I was not able to get it to feel right after bleeding everything so It may require more attention later on. For now the head is off the 258 so the cj is not really going anywhere fast.

I installed the bracket for the clutch and the extra support arm attached to the pedal assembly too. FOr the clutch, if you are trying to emulate me, you may want to oval out the two holes you drill to reduce headache. The other support bracket I actually went and measure off a yj tube where it is originally. It is in line with the top right bolt of the brake booster to firewall and is 7 7/8 inches away measuring from center tocenter. I needed my largest drill bit to make it fit through the fire wall(they arent labelled so couldnt tell you the size) and mounted everything up. This support rod can pivot on the brake assembly so i am sure you dont have to be exactly 7 7/8'' off the booster bolts but if you are going through the trouble may as well try to emulate a stock YJ in every way you can.

Unfortunately I cannot road test until I get a YJ clutch MC (right now have an XJ) and of course get the engine operating. I have no doubt that the clutch will function correctly after this assembly has been installed as Now it has the exact same pivot point as a factory YJ would have had. The brake booster wasnt a necessary upgrade but hey I had to pull the old booster off any how to punch out the CLutch MC slot so why not. I still have to revise my access plate for my twin stick shifters and will post that up once I make something.

Shot of everything hooked into the firewall

illustration showing everything that had to be drilled and the measurments I refered to above.

tried to get a shot of where the brace meets the assembly

shot of the pedals

shot of the rebent brake lines

This is what happens when your t5 blows up lol. I stopped keeping count but I think all total for parts and stuff, to include the ax5 I mistakenly bought and still have and the yj booster stuff this ran around 1200 bucks. So if you know how to rebuild your own tranny then you wouldnt save any money but if you were to have it done at a shop then you are definitely paying the same to upgrade. Now if this tranny goes it will be a direct replacement to fit another AX15! Thanks for all the positive feed back on this guys!!!