Clutch

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nickacb
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Clutch

Post by nickacb »

Hello everyone, I've seen that the part of the clutch noted in the picture is always tilted to the right, could it be that because it is currently straight the clutch is not working properly? (please don't mind the spring is there temporarly till I find one)

thanx
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Spider
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Re: Clutch

Post by Spider »

The Spring Anchor on the Arm won't be the issue here.

Looking at the angle of your Arm, I'd say the issue is the ball on the bottom of the arm and the hole the ball goes in to on the plunger are worn.

The Big Pin the arm pivots on would also likely be worn too.
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Peter Laidler
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Re: Clutch

Post by Peter Laidler »

Spider is dead right. Put simply, a bit of wear on the ball, the two axis pins, the axis pin hole in the push-rod and the axis pin hole in the clutch cover are small matters. But when operating together, this small amount of wear becomes a major operating problem. It is called accumulative error caused by the 6:1 (?) ratio of load-over-leverage

People just seem to try to live with it instead of fixing it properly. They bend the arm a bit and/or make a longer/adjustable push-rod....... Anything but fix the bloody problem.

Axis pins are easy to replace. Worn axis pin holes are simple to re-bush and the ball at the end is simple to weld and grind/file to shape.
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timmy201
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Re: Clutch

Post by timmy201 »

As mentioned above, the pushrod out of the slave is nearly at its limit in your photo. The arm is nearly 90 degrees to the angle of the plunger. The stop bolt on the clutch cover is wound out a fair way

Ideally when it’s all new the arm should be parallel to the clutch cover and only a short section of the pushrod showing

Mine was in a similar state (left side of photo)
With new and checked parts (right side)
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nickacb
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Re: Clutch

Post by nickacb »

Many thanx as always I gotta better notion of where to start.
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Joel Welsh 4769VU
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Re: Clutch

Post by Joel Welsh 4769VU »

The ball end they're talking about-
The end of the clutch arm inside- new and old, side by side for comparison.

You can see how worn flat my old one was on the right. I replaced it, the bearing, the thrust bushing it rode on, the clevis pin, the slave rod... all components in mine.

I went from no clutch movement at all, to function!
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Peter Laidler
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Re: Clutch

Post by Peter Laidler »

Thinking on my feet - again, I wonder........ Has anyone considered using a shell-mill cutter to machine away the end ball to leave a length of, say 1/4" spigot/shaft. Then put a tough round steel bush or ball onto the spigot. You could also bush the two axis pin holes at the same time.

Or just re-weld and re-shape.....

Or is the cost of a replacement cheap enough to treat it as a throw-away part?

Incidentally Nick, there are a few other things that you can do to make your clutch life much easier too. You'll have to search the forum though
nickacb
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Re: Clutch

Post by nickacb »

Thanx for the pic of the ball Joel, between my second lenguage English and my lack of mechanical knowlegde is easier to have a visual reference
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Joel Welsh 4769VU
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Re: Clutch

Post by Joel Welsh 4769VU »

nickacb wrote: Fri Feb 16, 2024 3:33 pm Thanx for the pic of the ball Joel, between my second lenguage English and my lack of mechanical knowlegde is easier to have a visual reference
Yes sir, i understand it.
I'm the same way- it's easier to see the connection that way.!
Wauseon, Ohio- United States
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I can't take credit for what others built- all I can do is try to put her back on the road. :shock:

You just can't fix stupid... you can hide it sometimes though... :lol:
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Spider
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Re: Clutch

Post by Spider »

Peter Laidler wrote: Fri Feb 16, 2024 10:44 am Thinking on my feet - again, I wonder........ Has anyone considered using a shell-mill cutter to machine away the end ball to leave a length of, say 1/4" spigot/shaft. Then put a tough round steel bush or ball onto the spigot. You could also bush the two axis pin holes at the same time.

Or just re-weld and re-shape.....

Or is the cost of a replacement cheap enough to treat it as a throw-away part?

Incidentally Nick, there are a few other things that you can do to make your clutch life much easier too. You'll have to search the forum though
The Ball Ends on the original Arms were hardened, I don't know to what 'number' but they weren't super hard. On some of the replacement Arms, this hasn't been done.

Just following on from your first idea here Pete, one could - if careful and skilled with a TIG - fit a Hardened Ball from a Ball Bearing.

I have a few times put some Hard Weld on the ends and linished them back to shape. It's probably out of laziness that I don't do that with all of them.

I'll add here that really, when you look at the design of them, they are far from idea. The after market types that have a flat shoe are in my view a smarter and more appropriate shape. The factory items were clearly a case of 'what's easy and cost effective to manufacture'.

The past roughly 10 years, the open gap in the Clutch Cover where the Arm is fitted, I've been stuffing some sponge rubber in to. Again, a bit of poor design, it's pretty much an ash tray there to grab all manner of road dirt and grim which goes so well in these parts (not). I've found the sponge rubber has increased the life of them considerably.
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Peter Laidler
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Re: Clutch

Post by Peter Laidler »

Another brilliant idea from your fertile imagination Spider Chris. I am going to do that rubber trick tomorrow. Did a similar thing with the top of the gear extension a couple of years ago after a small bolt dropped into it. But never thought of the clutch arm opening
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timmy201
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Re: Clutch

Post by timmy201 »

Another idea is to fit a hardened sleeve to the plunger like this. You'd rather have the arm as the wear point as they are much easier to replace.

Some of the new plungers are made much too soft
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