I seem to have had several issues after i did a t56 conversion on my 94 lt1, anyway I have replaced the master, slave, clutch disc and flywheel. The PP and TO were used before but with little wear. i have at this point bleed the system various times, both bench bleed and with a mightyvac. i am honestly about fed up with it. Also just to test it i removed the 2-2.5 inch bellhousing spacer and bolted up the slave as far as it would go, basically as far as the piston would move inwards inside of it, and once again it still wouldnt disengage the clutch. i am fairly sure the clutch is facing the right direction, the only thing I can think of is that i torqued the PP bolts to 25lbs, the book said 15, alldata said 22 i think, and the hays instructions said 35. It looks as though the fork is engaged with the TO....I give up...Any ideas?

 

The difference in decompressed disk thickness comapred to the compressed disk thickness is too big as a result of the marcels (thin springs between the facings) being out of spec. The two disk facings will decompress (again the marcels) when the clutch is disenaged, if the facings are not fully decompressed by the time pedal is released then the clutch will drag and cause this problem you are having. Bet its hard to get in gear and especially reverse huh.

Two options. Get an adjustable master cylinder that has more travel or throw. Or replace the disk with something in spec. The air gap or window on these pull clutches is super thin and if you cant pull the PP enough to clear the disk then you get drag.

Stock like disks all have marcels which look like z-bend springs between the two facings that reduce the chatter of the clutch but also weakens its grip some. High performance disks DONT have marcels so decompression of the disk is never a problem and grip is improved. A disk without marcels will NEVER encounter this problem since it will not compress.

I went down this road years ago and replaced the MC, SC, two PP's, TOB and bushings which all involved pulling the tranny at least 5 times. Drove me nugging futz. After I learned about the disk thickness with the Marcels, it all made sense.

Post a pic of the disk from the side showing the facing edges if you want.

 

ok heres a pic...http://static.summitracing.com/globa...y-40-221_w.jpg

yup I just checked and yea the reverse is very hard to get into

 

Wrong angle in the pic. The side of the disk (thin section).

 

crap well i don't have a pic of that

 

yep def. a macel thing between here's its info http://www.haysclutches.com/ProductD...minselection=0

 

I will nearly bet the farm you have a marcel disk and it is out of spec as stated above. Again the pull clutch release window is stupid tight and things must be very precise. Get out of that window and you get disk drag with the pedal pushed all the way down causing your problem.

 

That disk would work perfect for a pull clutch. But as you found out, not a pull type.

 

Will this occur even if the pedal feels normal?

Also, did you get your money back for yours?

 

The pedal will feel very normal with your problem.

The disk I had was a custom made disk, that according to the specs of the facings and the disk itself, should have worked. Yes the local clutch disk maker gave me my money back and then eventually gave me the disk which I sold to a guy with a run of the mill push clutch. If he had used a NON marcel disk,it would have been fine.

 

if I understand, I will got this problem too if I use my mcleod disk with my OEM lt4 pp..
please check my topic: https://www.camaroz28.com/forums/sho...d.php?t=669378

 

Its hit and miss to be honest if you have a marcel clutch disk that is NOT a genuine GM part. All you can do is throw it and see but be prepared to remove it if you get dragging.
This will never happen on a NON marcel clutch disk.

 

ok so just an update, I removed the metal piece that houses the slave cylinder and once again was able to push the slave in until it bottomed out, so maximumly inward. I then had my roomate push the clutch in as I observed and it definitely moved about 2 inches and pushed on the fork until it would actually grind against the pp. Once again not one hint of disengaging So its got to be the disc.

 

BTW any modding, spacing or jacking around with the slave cylinder, flywheel or the fork will do no good at all. No matter what you do, the automatic adjusting of the hydraulic clutch will adapt to the change and you will be right back in the same boat.

 

Yea Even tried spacing the transmission bellhousing out by putting washers between the two pieces so the fork would pivot back further from the TO bearing....no luck . So do you think I should buy a new clutch or get an adjustable master cylinder wrd.