My dad is planning to build a model of a Wilson pre-selector gearbox,
and asked me to look on the net for information about them. I tried
Google, which returned enough sites for me to reckon this newsgroup
might be relevant, but didn't seem to have any sites about the actual
gearbox and its technicalities.
Not sure what kind of help I'm looking for, but all contributions
I once had a 1948 Daimler DE27 Hearse, which used a 4 speed preselect gearbox, with fluid flywheel. She was quite a beast, and luckily for me, the transmission worked perfectly, without so much as an oil change since she was effectively 'dumped' back in the 1960's - couldn't get the right oil anyway without difficulty (engine ran on straight 30 grade - 20/50 would not do, no matter how much STP!).
She was a beauty to drive, once the steering box was replaced (same as a mil float oddly enough?), and the hydraulic brakes were working (front wheels only, back was mechanical - driving without front brakes NOT recommended with a four ton motor!). She pulled away smooth as silk, changed up and down beautifully, and reached 75 MPH with ease on the A1/A41, though not for the nervous! Only 4 to 5 MPG unfortunately, but a 30 gallon tank to compensate.
Good luck with the gearbox - I was told by an old boy (from Coventry) to be very careful tinkering with it... I asked where the oil drain plug was, and he said:
"Don't go undoing any nuts or bolts, there's one that IF you undo it by accident, 48 ball bearings and springs on this big shaft will spring out of their sockets... and you won't get 'em back...". This I believed, so I never dared touch the thing! All I can say it was incredibly complicated, but very robust, reliable and durable - and I never could find a workshop manual, or anything about it. Just as well it was never required!
I wish him the best of luck with this project, it sounds very ambitious... much respect!
I also wish I had her back... sigh... armoured glass, 1/4 inch thick, chassis built like a Tiger Tank, comfortably accomodated eight people (six sitting, two lying down), hand throttle (disconnected following alarming sleeve snag incident one day - shudder!), and massive 'proper' 17 inch split rims with 1944 tyres that were so thick, you could cut new treads on them (as a 'limited HGV' quite legal, and no MOT required, which was just as well!).
A wonderful machine... sniffle...!