AX5 clutch problem...need help UPDATE

[mjeff87]

Pete, feel free to move this to the Pub if you want,since it's not MJ specific tech but rather YJ.....

 

This weekend Chuck (cmcolfax), Jerry (tjbliley), and I did an auto-to-manual swap on Chuck's 95 (I think) YJ ->30RH (or something like that, 3 spd auto) to AX5. Got all the hardware in, Jerry figured out how to jump the NSS :cheers: , and got it fired up. Starter seemed to “knock” a bit when spinning, so we adjusted it (no shims) and that cleared up for the most part. But the big problem is that the clutch is slipping BADLY, like it’s barely contacting the flywheel. No power getting to the gearbox, and at idle in neutral with the clutch out, it will eventually start lightly smoking :eek: . Engine off, tranny in gear, you can even push the rig back and forth "freewheel"....no force back thru the gearbox to the engine. Flywheel, clutch master and line, and tranny all came from the same vehicle, and the clutch assembly (internal throwout) is brand new and the correct part #. TO is bled to spec, and the master is working correctly. Good pedal, and it pushes fluid well.

 

One thing I can immediately think of is that Chuck had the flywheel machined, and maybe the shop took off too much…..but it didn’t look any thinner than my flywheel which was machined also :nuts: . Another possibility is that the TO is hanging up (partially expanded) inside the bell, and is pushing on the fingers in the clutch cover. And lastly, there was a machined spacer on the back of the crank when we pulled the auto off that must have spaced the flexplate/tone ring out fir it all to line up….we didn’t reinstall it, because the donor rig didn’t have one and my MJ didn’t have one….the flywheel bolts directly to the crank-end in both cases. Chuck is gonna throw some pics up of the spacer sometime today, or send them to me and I’ll post them for view. We don’t really think that is the issue, because the problem is excessive clearance in the pressure plate/clutch disc/flywheel area, not flywheel to block.

 

Bottom line is that it all has to come back apart, but we’re trying to figure out what to look at when we do (won’t be for a few more weeks). Anybody have any ideas?

 

By the way, this is the first SWB Jeep I’ve had the (dis-) pleasure of working on :D ….and hopefully the last. Just isn’t any room to work on anything :headpop: !

 

Jeff

[cmcolfax]

First of all... a HUGE THANK YOU to Jeff for all of his help this weekend! And to Jerry for showing up twice just when we needed something!

 

:cheers: :bowdown: :cheers:

 

As for the description of the problem... well said Jeff... in fact I think I am gonna paraphrase that write up when I post up on a coupla other boards.

 

Pics will be up in a few minutes... just gotta put them up on my Verizon site and link them.

 

After doing a little more thinking last night... I can't seem to get the "spacer" out of my mind.

 

The TOB is attached to the gearbox and rides back and forth on the input shaft inside the bellhousing.

 

It has a finite amount of travel.

 

With the flywheel/clutch disc/cover assembly in it's current position (directly to the crank, no "spacer") the TOB is travelling all the way to it's maximum distance before it even begins to compress the fingers on the cover and sandwich the clutch disc between the pressure plate and flywheel.

 

Which is why it releases fine when the clutch pedal is depressed.

 

But does not fully engage when the pedal is released, thus causing the clutch disc to spin, loosly contacting the PP and FW, resulting in the burnt clutch smell and light smoke :eek: instead of it being tighly gripped between them.

 

It seems to me, if that "spacer" was installed between the crank and the flywheel, it would push the whole assembly .5" toward the gearbox. And the TOB would have to travel .5" LESS.

 

Since the clutch disc is LESS than .5" thick, that would allow for a tight "sandwich" between the PP and the FW.

 

BUT (and this is a big but) there is no mention of a "spacer" in the Haynes Manual, the FSM or Jerry's online parts list.

 

Any help here would be GREATLY appreciated... we won't be tearing back in to the driveline for a coupla weeks, so we have time to over-think, over-research and over-engineer a solution. :roll:

 

(And I'll make sure to stock up on BUD LIGHT instead of COORS LIGHT next time! :brows: )

 

-cmc-

[mjeff87]

Chuck,

Try this when you get a chance to see if it helps any.....open the bleeder on the TOB to take any pressure off (maybe push a little fluid out with the pedal and leave the bleeder open), then put the rig in gear and push it back and forth. See if the clutch tightens up and makes full contact (should try to spin the engine). That would indicate a hanging TOB.

 

Jeff

[cmcolfax]

PICS:

 

 

Yes, I know the flexplate/tone ring is backwards in the pic, but it was easier to show the relationship of the spacer this way.

 

 

Sitting on my PartsAmerica invoice for the new clutch kit...

 

 

-cmc-

[Eagle]

First off, y'ain't supposed to machine Jeep flywheels with the internal slave. I know it gets done ... and it always creates problems. HOWEVER ... the problem is usually the reverse of what you're encountering. The release bearing/slave assembly doesn't have enough travel to compensate for the machining. The usual "fix" is to shim the release bearing where it mounts inside the bellhousing, by an amount equal to what was removed from the flywheel.

 

This one is the opposite. First dumb question, but I have to ask -- you are absolutley certain that the clutch disc is facing the correct way? It only goes one way, and if it's reversed the result is essentially what you are experiencing.

[mjeff87]

I know, I know...but Chuck already had it cut before we started. (Side note...I know the AX15 'wheels are concave, but isn't the AX5 flat to start with?) Anyways, on the disc, I'm almost positive it went in correctly but can't say with 100% certainty because Chuck put it on while I slipped the housing over and lined up the bolt holes. I've never put one on wrong so I don't know what the results would "feel" like :D but it's a possibility :oops: I figured it would chatter and not engage smoothly if reversed, but still engage. As it sits, we're not getting any power into the tranny in any forward gear, but in R it *sounds* like the gears are getting at least a little...you can sort of hear the gears turning inside the case. But it doesn't move an inch.....

 

Jeff

[cmcolfax]

First off, y'ain't supposed to machine Jeep flywheels with the internal slave. I know it gets done ... and it always creates problems. HOWEVER ...

 

Ummm... didn't know that.

 

First dumb question, but I have to ask -- you are absolutley certain that the clutch disc is facing the correct way? It only goes one way, and if it's reversed the result is essentially what you are experiencing.

 

I was 100% certain... since it was clearly stamped "Flywheel Side".

But now I am second guessing myself... :roll:

 

I know, I know...but Chuck already had it cut before we started. (Side note...I know the AX15 'wheels are concave, but isn't the AX5 flat to start with?)

 

Chit. I didn't know... always had flywheels turned when doing clutches... in my CJ...

 

Anyways, on the disc, I'm almost positive it went in correctly but can't say with 100% certainty because Chuck put it on while I slipped the housing over and lined up the bolt holes. I've never put one on wrong so I don't know what the results would "feel" like :D but it's a possibility :oops:

 

:wall:

 

-cmc-

[cmcolfax]

Heh.

 

Three different people, on three different boards have asked about being 110% sure we put the clutch disk in facing the right way.

 

I am gonna :wall: repeatedly if that turns out to be our problem.

 

-cmc-

[mjeff87]

I'm working on acquiring a tranny jack, so all we have to do is pull the tranny/TC off as one....I'm NOT screwing around with that shifter bracket any more, or else the sawzall is coming back out :evil: and I have no love for dropping the exhaust again. If noone has one to lend, I'm just gonna buy an adapter jack from Harbor Freight for $35, and we can use it on your floor jack.

 

Hopefully, it'll be that simple. Yeah, right.....sure it will.

 

:D

 

Jeff

[mjeff87]

Well, here's an interesting update.....

 

(Pete, we need a "slap head" smiley in the list, especially for this)

 

It seems that the gurus at DC decided to equip the pathetic 30RH (a light duty, 3 spd auto, no OD mind you...) with a 23 spline output :nuts:

 

Chuck just did a quick visual to confirm, and it's true.

 

That's all well and nice, except we swapped in an AX5 in it's place, and reused the TC. As we all know, AX5's are 21 spline output.

 

So it seems that the clutch is working fine (although the light smoke is an interesting thing, maybe it's just the new clutch disk getting used to the flywheel surface?), but the tranny output is just sitting there spinning inside the 23 spline TC input.

 

Damnit! The thought never even crossed my mind to even CHECK to see if it was 23 spline. Just goes to show you should NEVER EVER second guess anything DC might have done.

 

We're now in the market for a 21 spline 231. Anyone have a spare lying around they'd like to trade for a 23 spline? :D

 

Jeff

[JOMJ87]

:fool: :thwak: There you go

[Oizarod115]

ouch.. thats no good. look for 90- t-cases. they should be 21 spline.

[mjeff87]

It lives :D

 

Chuck got the correct 21 spline TC in and bolted up.

 

It moves under it's own power (clutch is fine). No rear driveshaft at the moment (getting shortened to fit the SYE), but it works fine in "front wheel drive" :brows:

 

Pay no attention to the missing hood....and seats....and the battery that's hooked up with 2 pairs of vise-grips :dunce:

 

Here's a pic (that's Chuck, not me):

Jeff

Image Not Found

[cmcolfax]

C'mon Jeff... ya coulda linked the "action" pic!

 

 

Rear DS is getting measured today.

 

Sorry for this thread not being Comanche... but it is funny!

 

-cmc-