LS7 Clutch Will Not Disengage
#1
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I've been reading here and on a number of other forums trying to figure out my problem and I'm nearly at a loss.
Car: 1972 Oldsmobile Cutlass with LS1 and T56 out of a 2000 Firebird
Using an F-body master cylinder, and slave cylinder for hydraulics with an LS7 clutch and flywheel combo, all new parts,
I put it all together and was unable to get the clutch to disengage at all, the system should be correctly bled, I used the manual method followed by a Mityvac. Pulled the tranny and measured, to the best of my ability and it I determined I did need a small shim to make things work. Re-installed everything with the shim and bled the system over again. The clutch still is not disengaging but it is better than before by a little bit.
I've read that the stock master may not be strong enough to push the fingers on the pressure plate, but that seems "fishy" since there are tons of people that have had luck with this setup. I am thinking I either flubbed the measurements and need a slightly larger shim, or I may in fact need to sack up and purchase a Tick Mc. Any input would be appreciated, thanks.
Car: 1972 Oldsmobile Cutlass with LS1 and T56 out of a 2000 Firebird
Using an F-body master cylinder, and slave cylinder for hydraulics with an LS7 clutch and flywheel combo, all new parts,
I put it all together and was unable to get the clutch to disengage at all, the system should be correctly bled, I used the manual method followed by a Mityvac. Pulled the tranny and measured, to the best of my ability and it I determined I did need a small shim to make things work. Re-installed everything with the shim and bled the system over again. The clutch still is not disengaging but it is better than before by a little bit.
I've read that the stock master may not be strong enough to push the fingers on the pressure plate, but that seems "fishy" since there are tons of people that have had luck with this setup. I am thinking I either flubbed the measurements and need a slightly larger shim, or I may in fact need to sack up and purchase a Tick Mc. Any input would be appreciated, thanks.
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even though you have the stock master, you should still be able to disengage the clutch with all new parts and a proper bleed...does your clutch pedal feel spongy or have any dead spots? maybe your clutch pedal doesn't have enough travel to fully actuate the master cyl?
#6
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The stock LS7 clutch uses a SAC (Self-Adjusting Cover) and if the mechanism is maladjusted it will affect clutch function. Checking this will require the kit to be removed. You can then look at the springs, that are located radially on the plate, to determine if they are equally compressed. You can also take a picture and post it here or email it to me and I can help with further assessment. If the springs are not equally compressed/released then the clutch will effectively hang and thus not fully release.
#7
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Is it driveable? I put a new OEM clutch kit in my SS and I had to put a few hundred miles on it for the pressure point to come up. If its driveable but just hard to get in gear, and you know there is no air - I'd drive it around a little bit and see if it gets better.
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Had the trans out, remeasured and discovered I needed a larger shim. I can now get 2nd, 3rd, etc. 1stand reverse are still not in the cards, guessing I need to drive and let it self adjust.
#9
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The point of the SAC plate is that the engagement point is designed to be consistent over the life of the clutch. SAC units don't typically see the same geometric changes you see with non-SAC units.