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Discussion Starter #1
In my 355 I have the Zoom performance clutch, they had three levels and its the higher of the three. I have no prior knowledge with working on clutches and I did not install this one but the guy who did seemed to have done a good job with everything else. Anyway, I have driven many cars with clutches tho, none of them being anything other than stock, and right away I noticed that it didn't disengage or engage until it was almost completely out of travel... umm soon as my foot touches the pedal and just maybe a half inch of movement, but with no slack, would be all it took to engage the clutch. I hope you can understand what i'm saying.

Anyway, after installing the new sway bars I took her for a ride and romped on it a lil. Everything worked good so I parked her. today I made a run into town and when on the highway I went to pass a car and felt it rev up without any acceleration.. It then felt like it just wasn't disengaging all the way when i let off the pedal. and there is no play with the pedal at all. if anyone can understand what i'm trying to describe could you please inform me whether or not I can just adjust the rod that goes to the clutch fork or if theres anything I can do to maybe get her working better at least till I can afford to fix her right. It doesn't smell all burnt up although I did smell a lil oil smell when it was doing it. I think its just right on the edge of being engaged or disengaged and needs to be adjusted to allow more pedal travel, maybe so the clutch fork will back off the throwout bearing a lil more or whatever. i kinda understand the whole process but am looking for a lil confidence. Thanks for trying to decipher through my nonsense. I appreciate it!:confused:
 

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Clutch pedal always has to have free play in the pedal. I like mine with about an inch of free play myself. If you don't have freeplay your clutch will wear faster, much faster. Adjust the rod to move the throwout bearing and fork away from the pressure plate.
 

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Free play is measured at the pedal the factory starting point is 1" to 1 1/8".
Your pedal should come off the stop bumper this far before the throwout bearing touches the pressure plate fingers. I usually make the final adjustment so the car starts moving when the pedal is about 2-3" from the floor.
I think what you are describing is the adjustment rod (z bar to fork) is too long. Loosen the jamb nut and shorten the rod. If the adjustment is this far off you will burn up the clutch and the throwout bearing.
Russ
 

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Discussion Starter #4 (Edited)
ok guys thank you, now when I was under there I noticed that between the jamb nuts on the rod, and the header there is about an 1/16 of an inch. If I adjust the rod will I have clearance issues or does the rod not actually move but just the fork itself that adjusts? Its so hard to visualize for me cause everything pulls and pushes and pulls and pushes. lol anyway, Il just have to get under there and do it. I appreciate the feedback tho. I hope I can adjust the rod without it actually taking a farther position forward cause thats not an option.

oh and since theres no room to get any kind of wrench in there to attack those jamb nuts, will i be able to just pull the cotter pin holding the rod to the zbar, swing it down to adjust the nuts and then swing the rod back up to the zbar and re cotter pin her? Or will everything come apart lol. I have room to swing it down and adjust but was worried that the clutch fork would retract and notallow the threaded rod to return to the zbar without a fight. If iI have to leave it attached for the sake of the internals I will just remove the header itself for room.
 

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the rod just rests in the clutch fork(AS FAR AS I KNOW, thats what it looks like on mine, just a rod sitting in a bowl on the end of the fork)

so if you pull the cotter pin, the whole link comes out, and you can adjust it.

you should be able to get a little wrench in and break the nut enough to twist in while its in there though.
 

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depending on the parts used it's very possible you're not going to be able to adjust the clutch... it's actually sounding to me that the bell housing fork pivot needs to be longer...

flywheel thickness, bell housing depth, clutch overall thickness etc all have specs and sometimes they stack against you. if you find you have no way of adjusting it you'll need to pull the transmission and replace the pivot with this unit: http://www.summitracing.com/parts/mcl-16908

there are others on the market but unless the ball stud is as long as the unit shown you'll find they will only adjust within the specs of the factory pivot.

if you attempt the adjusting and find it's not going to happen, post back and we can go through the steps for pivot installation and clutch adjustment/pre-testing prior to the transmission going back in. no need to have to pull the transmission twice, we'll get it covered in a one shot deal...
 

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Discussion Starter #7
ill keep in touch

cool thanks you guys, ima see what i cant get outa this here set up, altho that would make sense needing something else. seems from looking at it that it might be out of area to adjust. its always felt like its been really close but never till today has it started spinning/slipping like that.
 

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keep driving it that way and you'll fry it...

take a look and see if it has a factory or aftermarket flywheel... are you using a factory bell housing?
 

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As stated by others, you've got to have free play in the clutch pedal to make sure the clutch fully engages. Is this an original standard car, or is it a conglomeration of parts cobbled together in order to get the clutch to release? If it's an original type clutch set-up you should be able to bolt in a replacement clutch without having to mess with the clutch fork or the pivot. The length of the throwout bearing is the first place I'd look. The one in there may be too long, common mistake.
 

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having insufficient adjustment would come from too short of a T.O bearing... not too tall...

there are only two T/O bearings used by GM passenger cars (not counting the obscure truck T/O bearing) a tall round faced bearing which is used on flat diaphragm clutches like on a Sixer and a short, flat faced T/O bearing which is used on the raised diaphragm clutch like what's found on V8's.

here is an image of all 3 T/O bearings. the G1625c bearing fits a '69 Chevy/GMC truck, a very obscure bearing, this is the exact bearing you'll find offered by some clutch companies to correct clutch adjustment issues when the specs stack against you due to aftermarket flywheels, bell housings etc. this would be used only if you can't get adjustment even after using the adjustable pivot.

left to right, the std V8 T/O, the six cylinder bearing and the truck bearing.

you NEVER use the round faced bearing on a raised finger clutch or the fingers/bearing will get accelerated wear and will wipe out both items.

flat fingers, round bearing, raised/curved fingers, flat bearing. Do Not mix them.


here is an image of the 2 GM bell housing pivots, and the McLeod adjustable pivot... the aftermarket adjustable pivots will only adjust to the specs of the two GM pivots, you have to use the taller adjustable pivot to correct geometry due to stacking specs. (you can try the taller GM pivot or the std adjustable pivot but you'll find in most cases that's a waste of time. so save time and buy the taller one first)



oh... and sad to say, if the geometry is off enough that the G1625C bearing is used, be prepared for shell shock... it costs approximately $100.00
 

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Hey flyer...you wouldnt happen to have pictures of flat fingers and rasied curved fingers, would ya?

http://tr6.danielsonfamily.org/5SpeedKitContents.htm

Never mind...I found some pictures.

I just put a clutch in my car, the parts guy gave me a flat face bearing for my flat finger pressure plate. He said it was correct and went as far as calling the tech line of the manufacturer. I was never convinced but its already installed. The Ram clutch I bought also had the flat face bearing but it was so cheap it fell apart while I was stabbing the tranny.
 

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If the throwout bearing is too long the pressure plate may never get fully released, hence no free play, or the play is in the linkage and not clearance between the TO bearing and the pressure plate.
 

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If the throwout bearing is too long the pressure plate may never get fully released, hence no free play, or the play is in the linkage and not clearance between the TO bearing and the pressure plate.
not disagreeing with you... it would take a real major error to sell a flat diaphragm six cylinder tall round faced bearing with a raised diaphragm or Borg & Beck clutch.

the tall round faced bearing wouldn't even be listed in the same catalog listing...

highly unlikely this is the case....
 

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Just trying to help Flyer. From some of the questions he was asking I am unsure that he fully understands what needs to happen in order to allow the clutch to engage and release properly.
 

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absolutely Brother... same here. not even trying to argue, just trying to make sure everything is clear for him. this clutch stuff can get aggravating enough as it is when we have issues... us guys trying to help don't need to add to that aggravation. ;)

i hope you're warm & dry out where you're at and are enjoying your day. ;)
 

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Discussion Starter #17
ok guys, good news. I went outside and decided I was just gonna dig into it. I removed the cotter pin pulled the threaded rod out from the zbar and clutch fork. I realized that the previous owner had scabbed this portion in because there was nothing but all thread, three nuts and the deal that screws on to the all thread and sticks through the hole on the zbar. the all thread on the clutch fork side was nothing more than ground down to be smooth like a rounded tip. no ball or nothing. Anyway I could tell that after pulling it down the clutch fork closed farther which is what I was after. the all thread needed to be shorter in order for the clutch fork to move closer to the zbar. i simply shortened it up but only about an 1/8 to 1/4 in. now my clutch pedal isnt so tight to the stop inside. there is actually a small amount of loose play. pedal feel is much lighter and it must now fully disengage because I have no more slippage when I mash the gas. Sooo im going to look and see if that part is something I can pick up because i would like it to be right but for now it cost me nothing and its cured the problem. thanks for all the advise guys and remember, just because its not stock doesn't mean its cobbled, its just custom!
lol no seriously, thanks for the confidence.
 

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Discussion Starter #18
its crazy because just shortening the rod up that small of an amount translated to over an inch of play in pedal. i believe the right throwout bearing and parts elsewhere were used, just that piece between the zbar and clutchfork was wrong. Im stoked cause its one more thing Ive learned to play with and before long il have gotten into everything. I don't mind not having to fix something unless i choose to tho, lol. That one was cutting it a lil close.
 

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Sounds as if you've got it figured out and now understand what needs to happen in order for the clutch to work properly. That's what makes this site so great.
 

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If your pedal is off the pedal stop bumper you will need to get a stronger return spring. If the pedal isn't held against the stop your throwout bearing may touch the pressure plate and burn up. If you are saying it comes off the pedal easily, that is the free play you are looking for.
The lower push rod kit can be bought at most aftermarket vendors (Some a kind of cheaply made). There are two styles : One is a threaded rod with a swivel, The other has an elbow with with a threaded rod.
Russ
 
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