17 replies to this topic

[Shooter63]

Something smiliar to that came out in a factory Technical Bulletin in about 1960 or 61 when the Arms still had bushes both ends.

Can I ask why the factory went away from the double bush?

Shooter

[mab01uk]

 

 

I have mentioned this before, but there is a very nice mod you do to the radius arm pin which does away with the need of the grease tube.
Countersink the original grease hole in the middle of the shaft, fit a brass pin into the hole and pean it to shut it off.
Put the shaft in a lathe, bore a hole the correct diameter to take a grease nipple and tap, make sure the hole is deep enough to reach the bearing, now cross drill the shaft to intersect your drilled and tapped hole central to the bearing, fit a grease nipple to the inner end, fit the pin as normal and pump grease in from each end. As you've shut off the original hole the grease has no option but to go into the bearings.

Shooter

I carried out this modification some years ago, think I saw it on the mk1 forum.
Well worth the effort. Fresh grease is injected directly into both bearings, rather than hoping some reaches a bearing.

I think that's where I first saw it, alot of what the guy came up with was wierd, but that made good sense.

Shooter

 

 

The second link below is the direct link to the Mk1 Forum technical guide which includes details of the mods to the radius arm shafts, but you may have to register first to access the 'The Knack' section of the Mk1 forum.

https://mk1-forum.net/index.php

 

REBUILDING YOUR RADIUS ARMS:-

https://technical.mk...ur-radius-arms/

Edited by mab01uk, 13 July 2025 - 06:35 PM.

[Spider]

Can I ask why the factory went away from the double bush?

Shooter

 

They had issues with lubrication and the bush would pick up on, then seize to the shaft. One of the issues with these and indeed the front arms  is that they are always 'loaded' under fairly high forces / pressures on the working face all the time, so when pumping on grease, it didn't go where it was actually needed, but around it. With the needle rollers, while not being ideal as a bearing element in this application, it does provide grease paths through the bearing , which are picked up as the bearing rolls over the grease.