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914World.com _ 914World Garage _ Too much travel clutch fork
Posted by: Kansas 914 Oct 19 2014, 01:45 PM
I have a friend that is trying to install a new (used) transaxle in his car. He is telling me that he has A LOT of free travel in the clutch fork before he feel any resistance from the T/O bearing touching the fingers on the pressure plate.
He has 3 washers behind the clutch fork pivot ball right now.
What can cause significant travel of the clutch fork before resistance? The clutch has all new parts (pressure plate, disk and throw-out bearing). The only part that is not new is the cup washer in the clutch fork. He said there is only about 1/2" space between the fork and the clutch fork opening before it hits the case when trying to engage the clutch.
Thanks in advance!
Posted by: orangecrate Oct 19 2014, 04:05 PM
I just replace that cup and it made a significant difference in the slop of my clutch fork. Mine had worn through and allowed the pivot ball to wear into aluminum of the bellhousing. I put a small amount of liquid steel in the hole to take up for the wear and back up the new cup and tapped it in. Problem solved. Don't get carried away with the liquid steel. You only need enough to fill in for the wear. Too much could cause more problems.
Posted by: Kansas 914 Oct 19 2014, 04:58 PM
I just replace that cup and it made a significant difference in the slop of my clutch fork. Mine had worn through and allowed the pivot ball to wear into aluminum of the bellhousing. I put a small amount of liquid steel in the hole to take up for the wear and back up the new cup and tapped it in. Problem solved. Don't get carried away with the liquid steel. You only need enough to fill in for the wear. Too much could cause more problems.
Thanks!
I told him to order the cup bushing and new cone screws while he is at it.
Posted by: pilothyer Oct 19 2014, 05:05 PM
Also don't overlook the two plastic pieces where the throwout mates with the fork.
Posted by: Kansas 914 Oct 19 2014, 05:12 PM
Also don't overlook the two plastic pieces where the throwout mates with the fork.
Jerry - I asked him about those 2 pieces and he said he bought them new - but the cup bushing got by him.
Thanks!
Posted by: pilothyer Oct 19 2014, 05:54 PM
Mike........That is quite a lot of free play with three washers stacked to correct the geometry even for a flywheel that has been cut to the max......I hate to be the bearer of bad news but if the new cup bushing doesn't cure the problem....I would be giving the flywheel a good look.........Also tell him to use some good sealant on those ballstud threads because that tapped hole goes all the way to tranny oil..
Posted by: Kansas 914 Oct 19 2014, 05:58 PM
Mike........That is quite a lot of free play with three washers stacked to correct the geometry even for a flywheel that has been cut to the max......I hate to be the bearer of bad news but if the new cup bushing doesn't cure the problem....I would be giving the flywheel a good look.........Also tell him to use some good sealant on those ballstud threads because that tapped hole goes all the way to tranny oil..
Jerry,
Flywheel is supposedly a virgin but I will confirm.
Good advice on the ball stud - I did not know that is was a through hole.
Thanks!
Posted by: Cap'n Krusty Oct 19 2014, 05:59 PM
having 3 washers puts the integrity of the threaded ball connection into jeapordy.
The Cap'n
Posted by: Kansas 914 Oct 19 2014, 06:02 PM
having 3 washers puts the integrity of the threaded ball connection into jeapordy.
The Cap'n
John,
I agree as there is no reason for him to have any washer there. New clutch kit and new clutch cable.
Posted by: pilothyer Oct 19 2014, 06:18 PM
Another dreaded thing to think about would be crankshaft end play (worn thrust bearing, improper endplay shims) After that I give up especially with new flywheel, new clutch disk, new pressure plate and known good throw out bearing. I am assuming the excessive play is noted when moving the fork by hand,
Posted by: Kansas 914 Oct 19 2014, 06:48 PM
Another dreaded thing to think about would be crankshaft end play (worn thrust bearing, improper endplay shims) After that I give up especially with new flywheel, new clutch disk, new pressure plate and known good throw out bearing. I am assuming the excessive play is noted when moving the fork by hand,
Engine was rebuilt 1000 miles ago and worked fine with the tailshifter that was in it before first gear went out. Replacement tranny (sideshifter) is displaying these symptoms. Yes only moving the shift fork by hand at this time.
Posted by: 914Sixer Oct 19 2014, 09:31 PM
There should only be one WAVE washer behind the ball stud.
Posted by: Mikey914 Oct 19 2014, 09:45 PM
Ok,
The additional washers are normally added to correct geometry for having material taken off a flywheel.
Correct me if I'm wrong but-
If more has been taken off the flywheel and no washer added the clutch will not disengage, hence the washer is added. If there is too much travel, perhaps he only needs 1 washer? Or just the factory wave washer if still in spec?
Posted by: Dave_Darling Oct 19 2014, 09:48 PM
Adding a washer is sometimes done to compensate for material removed when the flywheel is cut.
Originally, yes--just one thin wavy washer. A thicker washer may be needed in some cases, or even a thicker washer plus the wavy washer.
Three washers is just asking for the stud to pull out of the case, though.
--DD
Posted by: Dr Evil Oct 22 2014, 08:41 PM
Never seen 3 washers. What thickness? If thin, then not likely a huge deal. If thicker then that is a huge red flag.
If the flywheel has been machined that much, then the flywheel bolt heads will be hitting the clutch disk.
If I understand correctly, the previous transmission worked just fine and now after a swap of the clutch parts and a new box it is not working? If so, it would seem to rule out the flywheel.
When working properly, you should have some travel before the TOB hits the pressure plate, I cant remember how much. Best to hook up cable and see how the pedal travel is. However, address that 3 washer shit first. John mentioned the major risk with this.
Is the fork bent? Is the fork he is using one that came with the transmission? If so, can he compare it to the other transmissions fork?
Posted by: Kansas 914 Oct 23 2014, 05:55 AM
Never seen 3 washers. What thickness? If thin, then not likely a huge deal. If thicker then that is a huge red flag.
If the flywheel has been machined that much, then the flywheel bolt heads will be hitting the clutch disk.
If I understand correctly, the previous transmission worked just fine and now after a swap of the clutch parts and a new box it is not working? If so, it would seem to rule out the flywheel.
When working properly, you should have some travel before the TOB hits the pressure plate, I cant remember how much. Best to hook up cable and see how the pedal travel is. However, address that 3 washer shit first. John mentioned the major risk with this.
Is the fork bent? Is the fork he is using one that came with the transmission? If so, can he compare it to the other transmissions fork?
Hi Mike,
I asked him if the fork was bent because that could explain it quickly. He said it is flat and identical to the other one he has - so it is not bent. Not sure if it is the same one that worked before. I told him to get rid of the washers and get his geometry back to a normal baseline.
I am thinking it is something simple but he is 12 hours away so I can't just pop over and take a look.
I hope the move went well - exciting times for you and the family. Cheers!
Posted by: Bob L. Oct 23 2014, 12:21 PM
Since the other trans was working OK, maybe use the side shifter parts to convert the tail shifter to a side shifter, Or maybe try swapping the throw out bearing and fork parts to the new one.
Posted by: Kansas 914 Oct 23 2014, 01:27 PM
Since the other trans was working OK, maybe use the side shifter parts to convert the tail shifter to a side shifter, Or maybe try swapping the throw out bearing and fork parts to the new one.
The old tranny had first gear bad - but the clutch operated fine.
Something just isn't adding up on this one...
Thanks Bob.
Posted by: Bob L. Oct 23 2014, 02:06 PM
Since the other trans was working OK, maybe use the side shifter parts to convert the tail shifter to a side shifter, Or maybe try swapping the throw out bearing and fork parts to the new one.
The old tranny had first gear bad - but the clutch operated fine.
Something just isn't adding up on this one...
Thanks Bob.
You can swap out 1st gear while your at it. You will already be right there. Easy swap
Posted by: Kansas 914 Oct 23 2014, 02:10 PM
You can swap out 1st gear while your at it. You will already be right there. Easy swap
It is a bit intimidating for him. He took his old transaxle to a transmission shop in town - they opened it up and said - no way we can work on this - we don't have the right tools and put it back together.
I think it scared him off. But you are right - for someone that has had their hand in there before - probably not a big deal. I even pointed him to the Bird Board where they have a tutorial for 1st gear replace but it was too much.
EDIT - Here is a link to the Pelican Tech Article: http://www.pelicanparts.com/techarticles/914_tranny_repair/914_tranny_repair.htm
Posted by: Dr Evil Oct 23 2014, 08:00 PM
Is the TOB installed backwards?
Changing anything from side to tail is useless. The only things that matter in this whole equation:
Bell housing to engine dimensions - there should be no difference in the bell housings.
Forks - you said they are flat
Fork bushing - you said new bushing
Pivot ball - if there is a difference in this piece between the two boxes then swap the one that worked.
Washers - no more than 2 standard thickness, and that is if flywheel was resurfaced.
I seriously wonder if the TOB was installed backwards.
Posted by: Mikey914 Oct 23 2014, 10:45 PM
The washers change the geometry significantly. What I was trying to say on the last post is have you tried it with maybe one washer, and was it better or worse. I suspect you only need one or two at most. It sounds "over shimmed" to me.
Posted by: Kansas 914 Oct 24 2014, 08:37 AM
The washers change the geometry significantly. What I was trying to say on the last post is have you tried it with maybe one washer, and was it better or worse. I suspect you only need one or two at most. It sounds "over shimmed" to me.
I didn't know the T/O bearing could go on wrong but he is going to check it this afternoon when he removes ALL the washers and installs the new clutch fork cup washer.
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