Newbie here...can't get clutch to disengage...

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340_833 dart

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I sure wish I had found this site earlier.
Anyway, I recently completed an auto to 4 speed swap in my '73 Dart Sport 340.
I have the recommended 5/32" free play at the clutch fork.
When the clutch pedal is fully depressed, the clutch fork moves only one inch, which does not move the throwout bearing enough to get the pressure plate off the clutch disc. As a result, I cannot get the transmission into gear with the engine running without grinding the gears.
I'm running a Ram billet steel flywheel with a Hays street/strip clutch assembly.
The pedal rod, Z-bar, both Z-bar ball studs, nylon bearings, adjuster rod, return spring, clutch fork and clutch fork pivot are all brand new.
The only used pieces in the swap are the transmission, bellhousing and pedal assembly.
I used offset dowels to get the runout in the bellhousing down to 0.003".
What am I missing?

Thanks.
 
I had to adjust the threaded rod all the way out on my 4 speed.Everything is new on mine also,it works fine.But I find it very odd,cause now I have limited adjustment.
 
I've seen that problem a couple of times. One clutch fork wasn't properly installed and the other one had a bent fork. Both were Fords but still could be a clue. Good luck
 
hi, you might haveto lengthen clutch rod some. another area is the z bar. the arms are not equal length. upper is usually longer vs the lower arm. mopar recommends lenghten the lower arm pivot 1" to help the clutch to release.
on my duster I lengthen the lower and shortened the upper arm about 1" this gives you a lot more pedal travel. It will cut the travel in half usually. just something to consider.
 
perfacar said:
hi, you might haveto lengthen clutch rod some. another area is the z bar. the arms are not equal length. upper is usually longer vs the lower arm. mopar recommends lenghten the lower arm pivot 1" to help the clutch to release.
on my duster I lengthen the lower and shortened the upper arm about 1" this gives you a lot more pedal travel. It will cut the travel in half usually. just something to consider.
Click to expand...

Hmm. I hate to cut up my brand new Z-bar but, if that's what it's going to take, I'll do it.
The only problem with lengthening the lower arm is that it is already very close to the TTI headers.
I'll figure something out. Thanks for the advice.
 
perfacar said:
hi, you might haveto lengthen clutch rod some. another area is the z bar. the arms are not equal length. upper is usually longer vs the lower arm. mopar recommends lenghten the lower arm pivot 1" to help the clutch to release.
on my duster I lengthen the lower and shortened the upper arm about 1" this gives you a lot more pedal travel. It will cut the travel in half usually. just something to consider.
Click to expand...

This is from the chassis manual i assume? i think i read this before, but i'll have to look into it again:read2:
 
hi, If no room on bottom arm, then shorten upper arm. the thing is, you're changing the ratio and can gain pedal travel. first thing is to adjust the rod out to maybe get release. last thing would be to change pivot. you don't have to cut the arm, just drill a hole and put the pivot in new hole I found a used z bar and redone it. yes, this is from mopar race manual. I have seen some z bars where the bottom pivot is not down to the end of arm. my 273 dart was this way. all I did was drill a hole and moved pivot to it. didn't need to add to arm length.
 
perfacar said:
hi, If no room on bottom arm, then shorten upper arm. the thing is, you're changing the ratio and can gain pedal travel. first thing is to adjust the rod out to maybe get release. last thing would be to change pivot. you don't have to cut the arm, just drill a hole and put the pivot in new hole I found a used z bar and redone it. yes, this is from mopar race manual. I have seen some z bars where the bottom pivot is not down to the end of arm. my 273 dart was this way. all I did was drill a hole and moved pivot to it. didn't need to add to arm length.
Click to expand...

The gods must be against me with this swap.
First, I called the Hays tech line today to ask how much fork travel I need in order to disengage the clutch. The guy said, "Hmm, I don't know.":angryfir:
This evening, I've been working on the old Z-bar by changing the pivot points. I shortened the upper arm by one inch, and lengthened the lower arm by one inch and now the lower arm is binding on my TTI headers.
What confounds me the most is the fact that I cannot disengage the clutch, even though every single piece of the linkage is brand new and A-body specific.
 
Have you looked at relocating the pivot point on the frame rail forward a bit to gain clearance with the header.
 
momoparman said:
Have you looked at relocating the pivot point on the frame rail forward a bit to gain clearance with the header.
Click to expand...

Wouldn't that throw the Z-bar out of alignment?
I am going to need to pull the Z-bar, again, to shorten the lower arm back to the stock length. It just barely cleared the headers then.

Can somebody please measure how much total clutch fork movement they have?

Thanks.
 
Don't know.....I'm talking fractions of an inch of movement...

Something else to consider is that the arms on the Z-bar were misaligned prior to welding......can you cut one loose and relocate/tack it till you get the throw and clearance you want?

Tell you what....after building my fish I can tell you that NOTHING fits the way it should......I have modified every part I have purchased so far.....in one small or large way.....so don't be discouraged. This is typical.

Mop
 
How much peddle travel do you have? I would suggest your problem lies in the peddles or perhaps length of peddle rod to z-Bar??
 
MACKIN said:
How much peddle travel do you have? I would suggest your problem lies in the peddles or perhaps length of peddle rod to z-Bar??
Click to expand...

When I adjust the linkage to give 5/32" free play at the clutch fork, the pedal has about one to 1.5" of free play.
I have full pedal travel, meaning it goes all the way to the floor.
Even if I take up all the slack at the fork, it still does not disengage the clutch.
I've got to figure out a way to get more stroke out of the lower arm. The only way I can see to do that is change the pivot points on the Z-bar.
But, because everything is brand new and specific to the A-body, it should be working and it's not. That's what is driving me crazy.
 
hi, this might sound bit off, which way is the disc in? does the thick part face to the rear ?if you have changed ratio, and lengthened the rod and still hangs up, only place left is the fork or throw out bearing or the disc is in backwards. I assume you have a stock bellhousing ?can you look up in there? have someone push on pedal see how much it moves.also, did the disc slide easily on input splines?
 
The problem might not be the linkage. It could be that the nose of the tranny input shaft is binding in the pilot bushing (in the end of the crank) and then the input shaft doesn't stop turning when the clutch is disengaged. Did you have any problems, as far as things being tight and not wanting to go together, when you bolted the tranny to the bell housing.

Terry
 
"But, because everything is brand new and specific to the A-body, it should be working and it's not. That's what is driving me crazy."


Every part that I bought for my A-body construction that was SPECIFIC to the A-body had to be massaged in one way or another....I am looking at a POLY LOCK transmission mount, sitting on my desk that I paid $70.00 for that's a bolt in (supposed).....to what car I have no idea....supposed to be for mine. I ended up making my own trans mount out of bar stock and flat steel...SOLID.

I agree with the other issue.....could be the clutch itself not installed properly.....if not modify the z bar....you won''t be the first person to have to do this to a new part....trust me.
 
perfacar said:
hi, this might sound bit off, which way is the disc in? does the thick part face to the rear ?if you have changed ratio, and lengthened the rod and still hangs up, only place left is the fork or throw out bearing or the disc is in backwards. I assume you have a stock bellhousing ?can you look up in there? have someone push on pedal see how much it moves.also, did the disc slide easily on input splines?
Click to expand...

The bellhousing is stock. The Hays disc slid easily on the input splines.
Every time I make some kind of adjustment I always get my daughter or wife to push the clutch pedal while I'm under the car to watch the pressure plate.
It moves some, but not far enough to even let the clutch disc fully unload, much less moving enough to give air space between the PP and the disc.
I'm thinking about changing to a hydraulic set up and be done with all the mechanical linkage.
 
If you can afford it that's the way to go......consistent smooth pedal....never any fade....small and easy to get installed + no more sloppy linkage.

Have you ever rode a KTM motorcycle with one? They are so awesome.
 
hi,another thought, is there a broken finger? what type pressure plate? next question, If you install a hyd system and still doesn't release? here's a thought, if the disc is in backwards, it will not spin or release no matter how far you depress pedal. I'd pull trans, and drop clutch out first, make sure there is nothing wrong. you didn't say which way the disc was in. the pressure plate is going to move about .080- .100 for release. most adjustment calls for .080 between disc and pressure plate, with pedal fully depressed. can you slip a .080 feeler gauge between disc and pressure plate or flywheel? I set my clutches with a feeler gauge thats the most accurate method. freeplay doesn't enter in this method. like other comment, pilot shaft could be bound up in back of crank.
 
Success!
I ended up doing a bit of adapting to the mounting point for the clutch pedal rod.
I lowered the attachment point about 1 inch. That increased the stroke of the rod which, in turn increased the movement of the clutch fork and freed up the clutch.
Unfortunately, it started raining here about a half hour ago, so I can't road test the car. But I started it in the garage and was able to move the car back and forth with absolutely no grinding.
I couldn't do that before.
However I might just go ahead with plans to eventually install a hydraulic set up.
 
Something similar happened to me with my Jeep CJ and a replacement Peddle rod link.Glad you got'er figured out
 
Good work....time and patience and a lot of bad advise will eventually lead you to the truth.

Mop
 
Thanks for the effort... I'm having the exact same issue with the same clutch setup... It's gotta be the fulcrum arms on the Hayes pressure plate requiring more travel as I didn't have any issue with my old diaphragm clutch setup.... I'll adjust my Z bar and hopefully it'll fix my problem as well!!!

Thanks!!!!
 
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