1994 AX5 to AX15 Conversion - Page 5

**UltimatE** · 11-01-2009, 02:48 PM

Max, and everyone else, thanks for your help in diagnosing so far. This forum is amazing. Pretty sure Max nailed it on his last post about something being out of alignment.

I believe I have found the problem. When I bolted up the transmission to the bell housing, I failed to notice I was missing one of the alignment pins, the one in the upper right pictured below in Moonshine's photo. This caused the bellhousing to be rotated by ~1/16" clockwise.

There's something missing here.......................

That's MUCH better! Stole this locating dowel out of the AX-5.

Reassembly begins... Hope for the best =)

**UltimatE** · 11-01-2009, 04:40 PM

Holy jesus that was EASY... I got the transmission up on a jack and it slid into the pilot bushing like GLASS. Took only 5 lbs of force (to move the jack forward) to get it on.

**Mean Max** · 11-01-2009, 07:57 PM

I sure hope this gets you squared away, and I hope you can appreciate all you're learning (and I am too!) by working through all of this!

Max

**UltimatE** · 11-01-2009, 08:32 PM

Everything installed, same exact issue. Square one.

**Mean Max** · 11-01-2009, 08:37 PM

Quote:

Originally Posted by UltimatE

Everything installed, same exact issue. Square one.

I am feeling your pain.

I'll have it running through my brain all night, but for now I'm out of suggestions.

Max

**UltimatE** · 11-01-2009, 09:51 PM

And to top off the night I found my passenger side motor mount to be completely shot... so the engine is half hanging by a hoist.

**Opihi59** · 11-01-2009, 11:19 PM

So did you replace the pilot bushing with a bearing, or hone out the bushing with a brake hone? If the snout of the transmission fits into the bushing/bearing easily enough, it does not seem that it could get enough "bite" on the snout to be able to turn the input with much force-certainly not enough to make the Jeep actually move.
If you are able to disengage the clutch enough so the Jeep doesn't creep when the transmission is in gear, it may be adequate, so drive it some and see how it feels. You described that the clutch pedal had to be pretty far up in its travel arc to be able to get the clutch to "grab" so it would seem the clutch slave throw is long enough. If the throw is too much, then the TO bearing will continuously run against the pressure plate fingers and wear out early. Only thing I can think of otherwise is to shim the pivot ball forward--that is the knob on the opposite side of the clutch fork from the clutch slave. On a lot of systems I have worked with in the past, these are adjustable in their position.
Only other thing I can think of is significant warpage in your clutch plate itself--this can happen when installing a tranny and letting it "rest" or sag against the clutch plate, etc when you are struggling to install the transmission and have to take a break from lifting, pushing, shoving it forward to get it to line up with both the clutch plate splines and the pilot bearing. I know you described it going easy this second time, but was the first install easy as well? One way to tell is on subsequent tear down if your clutch has glazing in just a few spots, this would represent the high spot of the warp. I've seen this, it is a zebra* but since you're having problems, you gotta consider everything.

*Zebra--if you hear hoofbeats in the night, most likely it's gonna be horses, but on really rare occasions, it could be zebras, if you get what I mean. Consider the horses first then start looking for zebras.

The mechanical advantage in a clutch system is fairly significant. The pedal moves a long way to move the clutch slave, and by the time the motion gets to the clutch itself, the pressure plate only gaps open just a wee bit, like no more than a MM or less. There isn't a lot of tolerance down at the action end of the system.
You may find that once it is hooked up to the driveshafts and you run it around the neighborhood a few times, or on short trips, it will be fine.
It is hard to try to figure these things out from afar and over the internet, and both Max and I would like to be under the Jeep with you at this point. Hope it isn't too cold in Mass right now. Also, if you do have a broken motor mount, good that you discovered it this way. I know it's annoying, but isn't too bad of a fix.

I have boogered up the install of pilot bearings, I have a thread of it: http://www.jeepforum.com/forum/f12/p...lation-513450/

**Mean Max** · 11-02-2009, 07:07 AM

^^X2^^

I concur! Great advice!

Max

**UltimatE** · 11-02-2009, 07:52 AM

Quote:

Originally Posted by Opihi59

So did you replace the pilot bushing with a bearing, or hone out the bushing with a brake hone?

Nope, I reused the same pilot bushing. When I removed the flywheel from the engine and dry fit it to the transmission, it slid on without a single fuss, and spun freely. I figured the crooked bellhousing was enough to force the input shaft off at an angle -- Apparently not.

If you are able to disengage the clutch enough so the Jeep doesn't creep when the transmission is in gear, it may be adequate, so drive it some and see how it feels.

The Jeep does want to creep forward when starting, and there is significant pressure on the shifter such that I cannot shift sitting still with the clutch pedal pressed in and the engine running.

Only other thing I can think of is significant warpage in your clutch plate itself--this can happen when installing a tranny and letting it "rest" or sag against the clutch plate, etc when you are struggling to install the transmission and have to take a break from lifting, pushing, shoving it forward to get it to line up with both the clutch plate splines and the pilot bearing. I know you described it going easy this second time, but was the first install easy as well? One way to tell is on subsequent tear down if your clutch has glazing in just a few spots, this would represent the high spot of the warp. I've seen this, it is a zebra* but since you're having problems, you gotta consider everything.

I did notice some very minor glazing spots on the clutch plate on the teardown, where as the rest of the plate looked to be fresh and new.

*Zebra--if you hear hoofbeats in the night, most likely it's gonna be horses, but on really rare occasions, it could be zebras, if you get what I mean. Consider the horses first then start looking for zebras.

The mechanical advantage in a clutch system is fairly significant. The pedal moves a long way to move the clutch slave, and by the time the motion gets to the clutch itself, the pressure plate only gaps open just a wee bit, like no more than a MM or less. There isn't a lot of tolerance down at the action end of the system.
You may find that once it is hooked up to the driveshafts and you run it around the neighborhood a few times, or on short trips, it will be fine.
It is hard to try to figure these things out from afar and over the internet, and both Max and I would like to be under the Jeep with you at this point. Hope it isn't too cold in Mass right now. Also, if you do have a broken motor mount, good that you discovered it this way. I know it's annoying, but isn't too bad of a fix.

I have boogered up the install of pilot bearings, I have a thread of it: http://www.jeepforum.com/forum/f12/p...lation-513450/

I started the Jeep with JUST the transmission installed with the starter, slave, and CPS. It shifted just fine with the engine running. It wasn't until I installed the transfer case and rear driveshaft that the symptom returned. I believe the problem was still there, it just didn't have any resistance to present itself?

**Opihi59** · 11-02-2009, 08:40 AM

Quote:

Originally Posted by UltimatE

I believe the problem was still there, it just didn't have any resistance to present itself?

Likely so. Have you been able to drive it any?

I'm going to read back thru this and a few other similar threads and see if I can come up with any helpful ideas.

**UltimatE** · 11-02-2009, 09:54 AM

yea I just took it for a test drive. Clutch actuates just fine, grabs at its normal spot 3/4" to the top of the throw. Still has some sort of torque being applied to the input shaft though.

**Opihi59** · 11-02-2009, 10:23 AM

[QUOTE=UltimatE;8141933]

I used:

1994 2.5L Flywheel
Advance Adapters pilot bushing
1984 Camaro 4cyl Clutch disc, 9.125" diameter.
1994 2.5L pressure plate
1994 2.5L release bearing and actuator arm
1994 2.5L clutch master/slave cylinder setup
1997 Dodge Dakota bell housing
1991 AX-15 with external bearing retainer plate
1991 NP-231

QUOTE]

I'm a bit curious--is there any difference in thickness between the 84 Camaro clutch disc and the Jeep? Is there any way you can find if there is a difference in "travel" of the pressure plate between what would have been used in the Camaro with a "pure camaro setup," versus what the travel of the pressure plate would be in the Jeep? You may have everything set up as perfectly as it can be, but if there isn't enough travel in the pressure plate for that thickness of clutch plate, it won't fully disengage until it wears the clutch plate down a bit. You used a Jeep TO bearing--do you have a way to do a side-by-side with the Camaro TO bearing used with that particular system in a Camaro setup? Reason I ask is that if the contact portion of the TO bearing to the pressure plate has a wider diameter, then it contacts the P plate fingers more peripherally, which results in a shorter throw of the p plate since the fingers come together is a sort of cone fashion, which projects towards the rear of the vehicle. If the TO bearing contacts more peripherally on the cone, it will result in less throw of the p plate than if it contacted more centrally. I know this may require a shot or 2 of bourbon and a few sheets of paper to draw on to make sense, but I'm trying to get into the Zebras and this is the only way I can see/troubleshoot the problem by going thru this piece by piece.

Any input from those on the forum who have done this conversion (PMs) and issues they may have had?

I haven't seen an AX5 flywheel, unless what was posted up by Moonshinefuel in his NV3550 swap counts--is yours a stepped flywheel, or one flat planar surface all the way across? I had an irritating issue in the early 70's with a (ahem..) Vega stepped pressure plate that got machined improperly and it ate clutches and TO bearings with an insatiable appetite until I got a new flywheel.

And finally--if it presents no safety issue, can you just drive it for a while and see how it performs for you as things perhaps improve.

Don't get too frustrated with this, you are working in the right direction. Don't be embarassed to ask any question, we're rooting for you and want you to succeed.

moonshinefuel · 11-02-2009, 12:57 PM

When you push the clutch in all the way to the floor in gear, it feels like the jeep still wants to pull.
I do not believe this is your pilot (but not sure), you tested for fit, and also mentioned it mounted to the engine smooth as glass or something like that. As mentioned above, your clutch is not working properly possibly. Why don't you do this for me so we can establish throw. This picture is of the same components you have. Stick a tape measure in through the slave mounting area like this. Rest the end of the measure against the front face "lip" of the "cup" of the release arm towards the end. You should get a measurement close to this with the throwout bearing resting against the pressure plate. I have to go to the gym, and will be checking in again later today to try to help as well with what you are dealing with. Try to get this measurement to see if this can be eliminated as a possible cause. It should be very near this. (dont let the measure drop into the cup of the release arm, just rest it against the outer front area.)

moonshinefuel · 11-02-2009, 04:15 PM

I don't think the clutch is is a different thickness, it shouldn't be anyways.
I did just have a thought though, you didn't put the clutch disc in backwards did you? Now I have never done this, but it will fit the wrong way. Could this be a reason?

**UltimatE** · 11-02-2009, 09:51 PM

Quote:

Originally Posted by moonshinefuel

I don't think the clutch is is a different thickness, it shouldn't be anyways.
I did just have a thought though, you didn't put the clutch disc in backwards did you? Now I have never done this, but it will fit the wrong way. Could this be a reason?

That was a thought when I disassembled the first time. I tested to see if it would fit flipped around, and it will not. The splines on the clutch disc sit farther out on one side, and will hit the pilot bushing before the disc sits on the flywheel when installing the pressure plate/clutch assembly.