Need expert trouble shooting tranny/clutch

Muncie m21 4 speed , and 12 inch GM clutch and pressure plate

Ok new centric 13/16 bore clutch MC, and wildwood, 7/8 bore pull type SC,

Works perfect after I bleed it, while holding the SC. rod moves in and out.

But when i hook it to clutch fork, and bracket, then press the peddle, my peddle and clutch fork barley moves.

When i installed the clutch , and pressure plate , I used an old input shaft to all
align the clutch and went in and felt good.

Can you experts throw some ideas at me to check/rule out.

I dont think its the new MC. and SC, they seem to work perfect, I am inclined to think i messed up thr TOB, or clutch alignment or something like that.

When i slid the tranny into the TOB/clutch splines, i had to turn the output shaft a smidge to line up the shaft to the clutch,it did not slide flush was about 1/2 inch gap.

If i pushed the tranny it would feel firm but would fit flush but as soon as I quit pushing, it would rest back at about 1/2 gap.

Did i mess up the alignment?

I should probably do the nasty and pulling the tranny again.To be safe?

 

I was afraid to crank it just in case I screwed something up. HEHE.

But I dont have the rear end in it atm .

 

I see perhaps three different issues...........one the travel at the Slave Cylinder ( will get to that later ) the second being whether or not the Transmission is going in all the way although you say it is when you push it in..........do you have bolts in it clamping it to the Bell Housing?.............a transmission when hanging will slide back a little.......and third have you changed the Length of the throw out bearing which could be part of your first problem.
I would turn it over by hand first keeping in mind you should keep it in neutral since with the lack of travel at the clutch it will not release via the pedal.

 

Tunrs over good .

The travel of the SC is 1.25 and MC is 1.4

The MC has .518 square inches, and the MC has .6010, so thats .862*1.4 = 1.2 inch travel for MC and 1.07 inch as far as i can figure?

So travel seems good?

 

A couple of things. First, do you have the right pilot bearing? A half inch gap is about what one would expect if the input shaft was hanging up there. Second, there are 2 Chevy throwout bearings, the long one for the Borg and Beck style clutch and the short for a diaphram. If you mix them up, either you will not have enough travel to disengage or it will be riding on the fingers all the time.

 

Hey Duffer the throwout bearing and pilot bearing came with the kit.Sorry i should have mention that

The pilot is the little brass one, not the big roller one?

And since the TOB came with it I did not think to measure it, so I cant answer that one.

And I used the old Buick v6 clutch fork it fit fine on the pivot ball, could that be the issue?

and if so should I get a different clutch fork?

 

As "duffer" and I mentioned the length of the throw-out bearing & collar are important......and since you probably can't see up in there very well it may all have to be measured from the outside.................Now here is another thing to think about , without knowing if you have already had this current combination running?.............the way your set-up is with the Smaller 13/16" Master and a larger 7/8" bore Slave is opposite the way I would do it .......meaning I would ....with the proper 6 :1 Ratio at the clutch pedal , have perhaps used as you did a 13/16" Master but would have matched it with a smaller 3/4" bore at the slave..........IE; more volume per stroke at the 13/16 " bore to push the 3/4" slave farther in travel at the clutch fork .......and one last thing that most people don't consider is the clutch fork is on a 2:1 ratio at the Bell housing ball or fulcrum point............meaning whatever travel you obtain at the slave gets cut in half by 50% at the throw out bearing once it goes through the fork!.......that is why gaining stroke volume at the pedal to push more fluid is so important............It takes about .500 of travel to release the clutch + whatever freeplay.......Check your throw out bearing first and see what you have.............Hope this all helps!

 

Ok been fiddling with it and it looks like the clutch fork and TOB are already in all the way as if it is already engaged with the pressure plate.

Could I have bound it up when i slid he shaft into the TOB , I cant really see up in there very well, But it acts like the TOB is not on the fork anymore.

I am going to pull it tomorrow and will report back.

Thank you very much so far

 

Unfortunately, the sizes of the two cylinders are only part of the equation. The lever arm on the master cylinder also comes into play along with the clutch fork. I like the cast iron Chevy truck forks because you have two positions to hook the slave rod to and the wedge fulcrum makes a nice sanitary installation with a lot of adjustment available.

Even despite working it all out on paper, sometimes it still doesn't work really well (I have a pretty stiff pedal in the 3B).

 

Ok pulled it.

I did not align it good enough, and was not going into the pilot bearing.and the TOB was not touching the pressure pate.

other then that . every thing looks great.

So I Ordered a new clutch fork, like the one you guys like, cast and has 2 holes .

Will report back when i put it back in

 

Hey got it all figured out.

Ok first the 1/2 gap was clutch not aligned .

2.. Duffer called it. even tho the TOB came with my kit it was to short

new long TOB works great.

Its all good now,