Chipmaster Tumbler Removal

It's not uncommon on Chipmasters' for the screw-cutting gear tumbler to leak oil from it's worn O-rings straight into the tray where you keep tools, lunch, etc. I armed myself with the two correct O-rings and set about it today, keeping in mind I can't do much at a time these days.

Drained the oil, got the 3 screws out that secure the flange (1371 Bearing, page 7, Gearbox : Casting and Levers). The drawing on that page and the previous one are a bit sketchy when it comes to how the tumbler assembly sits in the screw-cutting gearbox. I was hoping the Tumbler/Selector flange and shaft complete with gear (1538 Gear) may pull straight out, but of course it didn't. The outer flange part of the assembly (the part with the slots that you drop the spring loaded handle into to change gear) moves axially about 7mm or 8mm in and out and that's it. Attempt at removing the gearbox soon revealed the necessity to remove all the shafts, pulleys, etc mounted to it, and at that point I wasn't feeling too hot and chickened out.

I wonder now if I was going about it the wrong way?. The exploded diagrams in the parts manual shows on page 6 and 7 the assemblies involved. The two O-rings involved are (1671 Bearing O-ring 26-870) and (1672 Plug O-ring 27-850). These are both BS O-rings and easy to get hold of. Should I maybe be removing parts (1557 Tumbler Handle) and the associated 1745, 1725, 1727 and 1652 ?. This may the free the tumbler flange (1371 Bearing), allow me pull the (1640 Bearing Plug) out, replace both seals and reassemble.

What does the panel think?

Secondary, when its time to refill with oil, do I use the specified SAE 68 hydraulic Oil, or SAE 68 EP Gear Oil?

Thanks in advance for any help.

Edited By Peter_H on 27/08/2021 17:30:24

Edited By Peter_H on 27/08/2021 17:31:03

bump