W6 4 speed hand change gearbox problem

[swiftruss]

I have just bought a 1936 W6 that was last on the road in 1974. I have it running but 3rd gear refuses to engage.
Is this a known problem with this gearbox?
A sandwich plate has been inserted under the inspection cover which has been cut and bent to restrict the travel of the gears. This doesn't appear to be a factory part.
3rd gear still doesn't engage with the cover and sandwich plate removed.
Any guidance would be greatly appreciated. In particular, what to look for when the gearbox is stripped.
Thank you in anticipation.

[swiftruss]

On further inspection through the cover, 3rd gear moves sideways on the shaft and appears to prevent the dogs engaging. Does anyone know if there should be a spacer between 3rd gear and the adjacent gear to prevent any lateral movement.
I have ordered a parts manual from Dragonfly Motorcycles, I should get the answer from that when it arrives unless anyone can supply me with one in the mean time.
Many thanks for any help.

[swiftruss]

I think Ive solved the problem by adding extra shims to the shaft. I wont know for certain until its running again.
I am now in need of a spring compression tool to refit the clutch. Does anyone have any ideas of how I may compress the one large spring to enable the collar to screwed onto the shaft. Alternatively, can anyone suggest a suppler the proper tool or anyone who may have one for hire.

[swiftruss]

Many thanks to Mark from the club for responding to my query. I managed to refit the nut with a large washer behind the nut while screwing a bolt into the end of the shaft. It isn't an ideal solution as it could be possible to cross thread when starting. Thanks again Mark

[JulianS]

That tool sound just like the BSA tool.