The Stovebolt Site Forums The Shop Area The HiPo Shop I have a real head-scratcher of a clutch problem,

I have a ’64 Chevy Short Bed Fleetside truck running a ’94 Z28 T-56. I’ve come to you guys looking for help because this is such a sweet tranny, I can't believe I'm the first one to try this swap, and I’m at my wit’s end!

The truck has all the stock clutch, pressure plate, flywheel, TO bearing, and slave that is correct for the Z. In order to fit up cleanly to the firewall and easily attach to the clutch pedal linkage, I’m using a stock ’64 Chevy manual brake master for a clutch master. I believe this MC has a 1” bore, and the slave has a ¾” bore. But I’ve got several issues. There is about 6” of pedal travel in total from the top of the travel to the floor. When I depress the clutch, for the first 3-1/2” or 4”, it feels like it isn’t even hooked up, like it is just return spring pressure. Then it comes up firm, like it is building pressure, and in only about ½”-3/4”, I can finally shift it into gear. I continue to slowly depress the clutch, and in another ½”, I get the most God-awful racket… it sounds like the forks are into the pressure plate – and I still have an inch of pedal left!

So my questions – what do I need to do to get a decent pedal? I’d like 1-1/2” or so of free play at the top, and full disengagement 2-3” below that, if possible. This would give me about 2-3” of functional working stroke. Is this attainable with a hydraulic clutch? And what is causing the horrendous racket? Is the master over-extending the slave somehow? How do I troubleshoot this thing?

I sure need some advice here, guys – I’m about to pull my hair out! Thanks! Bill

did you bleed the air out
ron

There doesn't seem to be any air in it, Ron, but there is no bleedewr valve n the slave s I can't confirm it. I'm going to go get one of those Mi-T-Vac contraptions and try it - see if I can suck a bubble or two out. I'll let you know... Thanks for the reply.

Bill

Watch the slave cyl. rod as you push in the pedal to see where it starts to move. If it starts moveing as soon as you move the pedal then the rod length off the slave cyl. needs adj. or modifiing. If it doesn't move then you have air in the system. Find out what size the MC was on the Camero. There may be too much difference in sizes causeing too much motion in the clutch fork.

The hydraulic clutch I drive most often doesn't feel any different than the mechanical linkage type.

I agree with Wrenchbender, you may need to change the master cylinder to match what was in the Camaro.

If the slave cyl. is like the ones in the trucks in that era, the bleeder is an allen scrwe on top of the cyl. near the closed end.

you might be pushing the pressure plate fingers into the disc's springs because there's too much travel. Check it with a helper,
Scott

I just have to say that your not the first to do this swap. My brother has the same tranny in his 66' C10. I can talk to him about your problem and see what he did.

I have a clutch ? / problem i recently bought a 49 suburban stock 6cly 3 on the tree just got it running today when to put it in gear to see if it would move and NODDA felt like the trans or atleast the linkage was going in and out of every gear but it wont move attempt to move make any different noises even in gear clutch pedal out reving it up no movment or noise?? any advice im new to clutch driven them before never worked on them LOL

This is just a possibility... The closed driveline front u-joints are kind famous for being the weak point. If its snapped, you wont go anywhere in any gear, all youll hear is clunking,,or no noise. You also wont be able to see it from underneath, as youll have to slide the "bell" back to expose the u-joint assembly.

If the clutch master is a 1 inch bore, and the slave is 3/4, you will have much more travel in the slave than needed. Maybe try a new Master with a 3/4 inch bore to limit the travel of the slave, or try a slave with a 1 inch bore to work with your existing MC.

If this is for me i do not think its the u joint there is NO NOISE at all no clunking nodda just the motor running and reving etc could the clutch be stuck away from the fly wheel?? like i said im new to working on clutches

Yes Tony, that was for you.

Another possibility is a broken rear drive axle. Not too probable though.

tony,
Does the truck grind with the engine running and trying to jam it into gear without pushing in the clutch? Clutches don't usually get stuck away from the flywheel. They usually get stuck to it. On the transmission, there are 2 levers on the side that should have 2 rods which come from the shifter box on the steering column. Are all these rods attached? It's possible that you are shifting the column shifter, but it isn't hooked up to the transmission properly.

I havent tried to put it in gear without the clutch and the lever look hooked up to me i crawled under it to check out the underside and snapped some shots while i was down there the trans was pretty wet could it be empty on fluid?? How do i check and what do i replace it with liek i said im new to working on clutches
http://i89.photobucket.com/albums/k237/bigtony55/IMAG0164.jpg
http://i89.photobucket.com/albums/k237/bigtony55/IMAG0174.jpg

Ok i went and tried what you asked me today and still nothing no grinding no moving i had my buddy look as the lever going into trans to see if it was moving he said it was when i pushed in and out on the clutch could it be the throw out bearing or is the clutch just so work out it wont move the truck or is just stuck away from im baffled here ???

Clutches don't get stuck away from the flywheel. If the engine is running and you can put the truck into gear without pressing on the clutch, and the truck does not move... seems to me you either have a clutch disc with a seperated hub, or a broken pilot shaft. Either way, it is time to drop the transmission and have a looksee. It is fairly common for the clutch discs to shatter, or for the rivots to shear off the disc.

John

Ok thanks for the advice ill have to get it in the shop and tear the trans out

Don't ask how I know this but you will get same problem if disc offset is wrong (backward). The hub of disc will touch the flywheel bolts (noise when you step on the clutch) and will partially compress your pressure plate (excess free play).