Author Topic: gearbox clutch arm  (Read 424 times)

Online edboy

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gearbox clutch arm
« on: 07.11. 2018 20:15 »
my gearbox clutch pivoting arm is heading west. chewing up the alloy casing as it goes. the greased rod is being pulled inwards requiring constant clutch adjustment. this caused a wear cycle and seems a bad design. anyone had a go at gearbox cover repairs or tried a modification?

Online trevinoz

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Re: gearbox clutch arm
« Reply #1 on: 07.11. 2018 20:17 »
Ream or drill the cover and fit a bronze bush.

Online edboy

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Re: gearbox clutch arm
« Reply #2 on: 07.11. 2018 20:23 »
thanks for repy trev. have you done this? and is bronze the right material as the arm looks hardened.

Online KiwiGF

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Re: gearbox clutch arm
« Reply #3 on: 07.11. 2018 20:24 »
Ream or drill the cover and fit a bronze bush.

I second that, you may also need the arm ground round again, my engineer did this job but needed to put a lathe centre mark in the top (visible) part of the arm, not a biggie.
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Online trevinoz

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Re: gearbox clutch arm
« Reply #4 on: 07.11. 2018 21:06 »
I have done a few.
Be careful drilling the cover as there is not much alloy around the hole inside.
I use leaded gunmetal bushes from a bearing supplier.
The first I did I drilled to suit the bush but later I machined the bush  o.d. smaller to lessen the chances of breaking through the alloy.

Online Peter in Aus

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Re: gearbox clutch arm
« Reply #5 on: 07.11. 2018 23:45 »
I set mine up in the drill press to get it square and straight and drill it out using 1/2 drill and make a steel bush to fit, don't make it to tight just a firm push fit and use loctite. I have done 4 like this with no trouble.
Peter

Busselton West Australia
49 A7 longstroke
58 A10  SA

Online edboy

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Re: gearbox clutch arm
« Reply #6 on: 08.11. 2018 18:38 »
 my inclination is towards a steel bush rather than bronze. i now have to find some bar and search for the buried lathe at the back of the garage.

Online RDfella

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Re: gearbox clutch arm
« Reply #7 on: 14.11. 2018 19:09 »
Steel is likely to rust. May not be a problem internally if well greased, but will look bad outside. Bronze will last as long or longer (it is a bearing material)
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