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> V8 conversion - clutch problem
DickSteinkamp
post Jan 17 2019, 02:52 PM
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1988 SBC, KEP 9" flywheel, 228mm HP pressure plate, 228mm kevlar faced disc. TOB from Renegade matched to the KEP parts.

The clutch will disengage, but only very close to the bottom of the pedal travel. In fact, I had to remove the pedal stop. There is almost no free play in the pedal at this point. If I add more free play, the clutch will not disengage.

I understand the "fix" for this is to space the pivot ball towards the clutch. Is there any way to determine how thick of a washer to use? I'd dearly love to do this once. (IMG:style_emoticons/default/smile.gif)
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djway
post Jan 17 2019, 04:38 PM
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Have you checked to see if there is any movement of the clutch tube in the tunnel? Should not need that long of a throw to disengage.
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Chi-town
post Jan 17 2019, 04:52 PM
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Also how much free play is there at the fork?
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DickSteinkamp
post Jan 17 2019, 05:00 PM
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No movement of clutch tube in tunnel.

Not sure what you mean by "at the fork". There is about 1/4" free play at the pedal (pulling it up from its resting place).

I understand this is also a common problem on a stock car when the flywheel is surfaced. Generally a shim is added under the fork pivot ball equal to the amount taken off the flywheel.
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Chris914n6
post Jan 17 2019, 06:00 PM
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tighten the cable until it releases where you want it.
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DickSteinkamp
post Jan 17 2019, 06:12 PM
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QUOTE(Chris914n6 @ Jan 17 2019, 04:00 PM) *

tighten the cable until it releases where you want it.



I'll have no free play then. I would guess it would also start the TOB into the PP. Doesn't sound right.
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Chi-town
post Jan 17 2019, 07:56 PM
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I meant can you wiggle the release fork with the current cable adjustment?

You can adjust the cable till the TO bearing is just very slightly putting pressure but anymore will cause premature bearing issues.

I would call Kennedy and see what they say.
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djway
post Jan 17 2019, 09:29 PM
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I have seen that with a broken or dislodged TO bearing
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DickSteinkamp
post Jan 17 2019, 09:37 PM
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QUOTE(djway @ Jan 17 2019, 07:29 PM) *

I have seen that with a broken or dislodged TO bearing


I have the engine and trans out of the car and the trans off the engine. TO bearing is as new. and was in the proper position.
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sixnotfour
post Jan 17 2019, 09:38 PM
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plastic pivot bushing in throw out arm ??
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DickSteinkamp
post Jan 17 2019, 09:53 PM
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QUOTE(sixnotfour @ Jan 17 2019, 07:38 PM) *

plastic pivot bushing in throw out arm ??



Yes...and it is in good condition, but I'm going to replace it since I have it apart.
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djway
post Jan 18 2019, 02:32 AM
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Once TO contacts plate there should only be about 2 inches of pedal required to disengage so something is not correct.
What is the angle of the lever arm on the tranny when the TO meets plate? It should not be too far from resting point
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DickSteinkamp
post Jan 18 2019, 03:54 PM
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I poked around this morning and learned a few things...not the least of which is I've got a lot to learn. (IMG:style_emoticons/default/unsure.gif)

The probable primary cause of my problem was that I did not install the clutch bearing guides...90111682511. My car came to me without the engine, but the trans was still in the car. The guides were not there and I didn't know there were such things until I studied the exploded drawings this morning. It looks like they will move the TOB closer to the PP. On order now.

I also found out how to determine if I have the right clutch fork geometry BEFORE I reinstall the engine/trans.


If I still don't have the right geometry, there are at least a couple of ways of moving the clutch fork forward.

Post #17 here...


This thread...


And post 181 here...

Thanks everyone for your help. Hopefully I'll do the research next time BEFORE I start asking questions. (IMG:style_emoticons/default/smile.gif)
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Mike Bellis
post Jan 18 2019, 07:38 PM
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Do all your research and then put a washer under the pivot ball and be done... (IMG:style_emoticons/default/biggrin.gif)

BTW, washer thickness tolerance varies from tranny to tranny. You only put one and it may have to be shaved to get a full thread turn on the ball. Most of the opposing force is pushing down on the ball and not to the side. Put some red thread locker on it and call it good. You could fix it in 2 hours. Or if you prefer, you can research it for a few days... (IMG:style_emoticons/default/poke.gif)
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DickSteinkamp
post Jan 18 2019, 08:33 PM
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QUOTE(Mike Bellis @ Jan 18 2019, 05:38 PM) *

Do all your research and then put a washer under the pivot ball and be done... (IMG:style_emoticons/default/biggrin.gif)

BTW, washer thickness tolerance varies from tranny to tranny. You only put one and it may have to be shaved to get a full thread turn on the ball. Most of the opposing force is pushing down on the ball and not to the side. Put some red thread locker on it and call it good. You could fix it in 2 hours. Or if you prefer, you can research it for a few days... (IMG:style_emoticons/default/poke.gif)


Thanks, Mike.

The car is down for paint and the engine/trans is out so that I can prep the engine compartment for paint. I've got more than two hours of that ahead of me. (IMG:style_emoticons/default/dry.gif) . Part of the hobby for me is learning. This is my first 914 but I've probably done 30 other cars (stockers and modifies). I'm learning a lot abut these great cars...and having fun!

Yep, it may come down to throwing another washer under the pivot ball....and since you have been there/done that, it probably will. It's my first time to see the prob.
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djway
post Jan 18 2019, 09:45 PM
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QUOTE(DickSteinkamp @ Jan 18 2019, 01:54 PM) *

I poked around this morning and learned a few things...not the least of which is I've got a lot to learn. (IMG:style_emoticons/default/unsure.gif)

The probable primary cause of my problem was that I did not install the clutch bearing guides...90111682511. My car came to me without the engine, but the trans was still in the car. The guides were not there and I didn't know there were such things until I studied the exploded drawings this morning. It looks like they will move the TOB closer to the PP. On order now.

I also found out how to determine if I have the right clutch fork geometry BEFORE I reinstall the engine/trans.


If I still don't have the right geometry, there are at least a couple of ways of moving the clutch fork forward.

Post #17 here...


This thread...


And post 181 here...

Thanks everyone for your help. Hopefully I'll do the research next time BEFORE I start asking questions. (IMG:style_emoticons/default/smile.gif)

Just that part would make a huge difference in the geometry. If your pedal feels resistance only 1/4 inch in and does not release the plate until the pedal is on the floor no amount of shimming at cable will help as the arc is off for the TO bearing. The only other thing it could be at that point would be a broken cable that stretches under load or the clutch tube or bowden tube was broken.
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Mike Bellis
post Jan 19 2019, 12:32 AM
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QUOTE(DickSteinkamp @ Jan 18 2019, 06:33 PM) *


Thanks, Mike.

The car is down for paint and the engine/trans is out so that I can prep the engine compartment for paint. I've got more than two hours of that ahead of me. (IMG:style_emoticons/default/dry.gif) . Part of the hobby for me is learning. This is my first 914 but I've probably done 30 other cars (stockers and modifies). I'm learning a lot abut these great cars...and having fun!

Yep, it may come down to throwing another washer under the pivot ball....and since you have been there/done that, it probably will. It's my first time to see the prob.

Not every V8 setup needs it. I had to with my 9" Kennedy clutch but not with my other V8. I've had 3 different V8 setups over the years and only one needed the washer.

Now I'm all hydraulic so I'm no longer suffering from you affliction. Lots of smart people in this forum so you will learn a lot.
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DickSteinkamp
post Jan 19 2019, 09:24 AM
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QUOTE(Mike Bellis @ Jan 18 2019, 10:32 PM) *

Lots of smart people in this forum so you will learn a lot.


I've noticed. (IMG:style_emoticons/default/smile.gif)
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shoguneagle
post Mar 11 2019, 01:48 AM
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Got interested in your problems; currently converting my -6 to hydraulic clutch. I noted you mentioned you had not put the clutch bearing guides in and you mentioned it could be a probable cause. Did this fix anything you were having problems with?

It does sound like the washer shims under the pivot ball; I am going through similar problems on my conversion to hydraulic clutch. The only way you can accurately find correct shim is to fit it in and the put the trans in bolted on lower left and top right; then see is the adjusted clutch works properly. May take a couple of times but you will get it.

More than one washer shim, seal it because it opens directly into the transmission cavity. I am now going through what you have been going through AND I am not really clear on what the measurements are for the slave movement with the shift fork.

Thanks and good luck.

Steve Hurt
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