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Question about a T9 5 speed with a cable clutch. In adjusting the clutch cable when I was having trouble getting into reverse, I've found that the clutch release arm is hitting the bell housing and has actually put a small notch into it where it hits. It has to go this far in order to fully disengage the clutch, and I'm not sure that even then the clutch is fully disengaging as reverse is still a bit difficult. Is there an adjustment that I'm missing or is this a sign that the arm has somehow bent? Could the release bearing be causing this? Any suggestions? Thanks.

 

 

 

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A little different, but may be pertinent. On my T9 5 speed, with hydraulic actuation, a stop had to be added because the arm was traveling too far, over center, allowing the clutch to drag. The symptom was hard shifting. Adding a travel stop fixed the problem.

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A little different, but may be pertinent. On my T9 5 speed, with hydraulic actuation, a stop had to be added because the arm was traveling too far, over center, allowing the clutch to drag. The symptom was hard shifting. Adding a travel stop fixed the problem.

That's interesting. How did you know that was the problem? I added a pedal stop to stop the arm at the bell housing and that made it impossible to get into any gear telling me that the clutch was really not disengaging.

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After several removal and disassembly operations trying to fix hard shifting, replacing synchros, etc. Eventually figured it out noticing how the arm interacted with the throw out bearing the bearing interacting with the clutch. Move it too far, and the clutch re-engages somewhat.

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  • 2 weeks later...

Not sure if this applies for your application, but here is what I did to correct clutch problem alignment.

 

I had to make a longer pivot arm bolt to move the clutch arm closer to the pressure plate. Since the bolt is threaded, obtained a longer bolt and ground the head to match the profile of the old bolt. If the bolt protrudes through the back side of the bellhousing, ground a slot or a square so the bolt can be adjusted externally.

 

Wayne

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Wayne,

This is all a bit over my head so apologies if this is a stupid question. When you say pivot arm bolt is that the same thing as the clutch arm fulcrum pin which is attached to the bellhousing? I’ve seen a picture of the inside of the bellhousing and there is a washer behind this pin and I can appreciate how that would change the throw on the clutch arm. I’m interested in your solution on how to make it externally adjustable. Thanks.

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When I did my Honda K24 to a Miata trans swap I had a devil of a problem with the clutch. I had the engine out 3 or 4 times, tried new clutch master and slaves cylinders, also tried different master cylinder sizes. I finally went to the K-Miata shop (at that time Dave's garage). After a lot of head scratching Dave said I have a clutch arm around here somewhere. Both looked perfect, but when we out them on a flat surface we could see they were different. My clutch fork was causing over extension of the clutch and that did make the clutch drag. So it's not crazy that over extension can cause clutch drag. Try engagement at various pedal travels and see what happens.

 

Graham

DSCN1128.jpg

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Wayne,

This is all a bit over my head so apologies if this is a stupid question. When you say pivot arm bolt is that the same thing as the clutch arm fulcrum pin which is attached to the bellhousing? I’ve seen a picture of the inside of the bellhousing and there is a washer behind this pin and I can appreciate how that would change the throw on the clutch arm. I’m interested in your solution on how to make it externally adjustable. Thanks.

 

Yes, clutch arm fulcrum sounds like the proper term. It is really just a fancy bolt. The washer on the bolt stops it from going in to far and provides stability to the pin. If the threads go all the way through the bellhousing, the bolt can be stabilized and the length adjusted by using a stop nut on the exposed threaded portion. By filing a slot or square at the end of the bolt, its length can be changed without damaging the threads.

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Had time to test whether it is an overextension problem causing the clutch to drag and it isn’t. Will start taking things apart tomorrow. Another question though, why would warming things up make the problem worse, ie when first started getting into reverse works ok, possibly without the clutch arm hitting the bell housing in it’s full extension. After the car is fully warmed up and taken a few trips up and down the driveway, reverse is much harder to get into, requiring the full travel of the clutch arm until it is hard up against the bellhousing and then getting reverse only with a bit of a grind.

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  • 2 years later...

@Lotusfan, did you ever solve why it was worse with a hot engine? I'm experiencing the same thing. I recently had to do a master-cylinder rebuild in my 1990 X-flow Cateham with a hydraulic clutch (5-speedT9, DeDion). I also swapped out the slave cylinder since I had a new one in my stash of parts. Now, reverse (and somtime first) is hard to get into with a noticeable clunk, but clearly worse when the engine is hot. I've adjusted all of the play out of the mechanical linkage at the slave, and the friction point of the clutch is with the pedal about 2/3 away from the floor. Following advice from further back in this thread, I tested whether I might be over-extending the clutch. Experimenting with not pushing the pedal to full travel did not help. If anyone has any advice or experience, I'd love to hear your thoughts on what might be going on, or how to adjust the clutch mechanicals. Cheers.

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@Lotusfan, did you ever solve why it was worse with a hot engine? I'm experiencing the same thing. I recently had to do a master-cylinder rebuild in my 1990 X-flow Cateham with a hydraulic clutch (5-speedT9, DeDion). I also swapped out the slave cylinder since I had a new one in my stash of parts. Now, reverse (and somtime first) is hard to get into with a noticeable clunk, but clearly worse when the engine is hot. I've adjusted all of the play out of the mechanical linkage at the slave, and the friction point of the clutch is with the pedal about 2/3 away from the floor. Following advice from further back in this thread, I tested whether I might be over-extending the clutch. Experimenting with not pushing the pedal to full travel did not help. If anyone has any advice or experience, I'd love to hear your thoughts on what might be going on, or how to adjust the clutch mechanicals. Cheers.

Sorry, can't help you out. My car has a cable clutch. My problem turned out to be that the release bearing that was installed was not correct. I had ordered a replacement to have on hand when I had the engine out and when I compared them, the new one was a bit thicker. With it installed, the problem went away.

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You can help that with a wider diameter master cylinder. I just replace min on my 1987 De Dion, 1700 Supersprint and while the cluch grabs quickly I don't have your problem, even though I stuck with the original diameter master.

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David,

I'm not familiar with the clutch layout on your car, but I have see similar issues if there's air in the system.

 

You mentioned the "new" slave cylinder from your stash. Did you crack it open and inspect it? I had a battle with slave cylinders on my Midget due to substandard parts. They sort of sealed...

 

Andy

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Thanks Andy. I didn't open up the slave cylinder since I don't know if rebuild kits are available, good point, it could be the problem. Although the master is a typical Girling unit, the slave was made by an American company called CNC/Neal, which are now out of business, and as far as I can tell, catered to the VW/Dune buggy market. I haven't been able to find out anything about why Caterham used that slave cylinder, or even see pictures of other cars. I do know it was stock, at least for cars sold by Sevens and Elans. My car came from them (I'm the second owner), and I bought a master and the replacement slave from the[ATTACH=CONFIG]17763[/ATTACH][ATTACH=CONFIG]17762[/ATTACH]m 10 years ago when Chris T. was still in Massachussets.

 

Do other hydraulic-clutch CAterhams from a similar era (1990 X-flow) have the same slave cylinder? Her are some pics.

slave-original.jpg

slave-replacement.jpg

Edited by DavidL
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Do other hydraulic-clutch Caterhams from a similar era (1990 X-flow) have the same slave cylinder? Her are some pics.

 

My friends early 90's X-flow Caterham has the same clutch slave. He bought the car with very low miles from Christ T at Sevens and Elans. The original was leaking so we replaced it with the same setup as your replacement. I know we spent some time adjusting it before we could get it to work properly.

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Dave,

Is it possible the actuating rod on the new one is just a little longer? Maybe you're just at the limits of it's adjustment and not using it's full available travel from the slave. It looks like you could either play with the coupling nut, replace the current jam nut with a thin jam nut (or leave it off for test purposes) or cut additional threads on the actuating rod.

 

Andy

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Great, thanks for the feedback and confirmation that other cars used the same slave cylinder. OK, so job one is to re-examine the linkage and compare slave cylinder rod length with the old one... maybe they're different.

 

I appreciate all the help! -David

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