Having got the bike onto a secure rear stand, time to take out the 3 stud QD rear wheel...except the QD bit wasn't having it
. I removed the 3 stud nuts holding the brake drum to the hub, then the spindle and spacer from the offside. At this point, the wheel hub should have come away leaving the brake drum still bolted to the nearside frame lug.
Tapping it didn't seem to help, so eventually I decided to remove the complete wheel with drum still attached and investigate off the bike. In the end, I did manage to separate the two with gentle tapping of pins and sprocket. I think the 9 locating pins were just clogged with decades of dirt:
Wheel hub with drum removed showing the 9 locating pin holes and 3 larger holes for the threaded studs:
Back of brake drum showing pins and threaded studs:
Inside of brake drum:
I've been quite careful in documenting how all the pieces of the rear hub + drum bolt together and in what order. I'm fortunate in that all the pieces look to be correct, in good condition and correctly assembled. The 3 stud QD wheel and plunger frame seems to a rare combination and many of the parts are not the same as the 3 stud QD wheel on a rigid frame.
Top row shows the drum parts. From right to left is: the drum spindle, MJ7/8 ball bearing with shields either side and circlip, spacer on inside of brake plate, spacer on outside of brake plate (only fits one way due to step on internal bore), snail cam adjuster, nut. The spindle is hollow and accepts main spindle below.
Bottom row shows the hub parts. From right to left is: main spindle, fork sleeve locknut, snail cam adjuster, fork sleeve, main spacer.
I'll investigate the hub bearings tomorrow. Oh, and having got the rear wheel out, I can now see just how bad plunger link bushes can get --- I'd heard that they can wear out quickly leading to poor handling. Mine are shot to pieces