YAY!!!
I took the engine - with pulley attached over to a mate's place - he's got one of the best setups you'll ever see - plus a wealth of knowledge and experience.
We considered all the responses I've had and ended up assuming the pulley was just slid on to the original JAP crank. So we ended up hammering (and hammering....and hammering) a couple of chisels down in between the pulley and the crank case and got not movement
Applied some heat - heard a bit of a "crack" - more hammering and it began to move ever so slightly.
Of course once is started moving it wasn't so tough to get off.
Good show!
But as for now - bead blasting for the cowl and crankcase and start the prep for painting.
I'd consider soda blasting for the crankcase, too. The problem with glass beads is that they get stuck in all sorts of nooks and crannies, especially tapped holes. And they're buggers to get out of there!
If you aren't extremely thorough in cleaning them out, it only takes a couple of them to get into a bearing or such, to wreck it.
For de-rusting, if you're the patient [as in a couple of weeks to complete a job] type, there's an extremely simple, cheap, effective and environmentally friendly DIY rust-removing bath solution recipe about.
It's just stock feed grade Molasses [a byproduct of sugar refining], mixed with tap water in the range 1+5 to ~1+10 dilution. I've got one of these baths going at the moment, to de-rust some old tools and such. It cost me $11 for 5L of black molasses, and I've used 1.5kg of it in ~12L of water. One bucketful of hot water to dissolve the stuff, and a top-up from the garden hose. The bath does need to be set up out of doors, though [edit: it does stink a bit, once it starts to ferment]. And kept covered.
I've uncovered quite a few spots of the original paint colour - a kind of pale/steel blue - a metallic shade - I am thinking of doing it with GALMET Hammer Finish Reef Blue - seems a reasonably close match to the original - but how will it handle the heat?
Wouldn't expect it to have any problems on a cooling cowl. The crankcase does need to be done in 'engine paint', which is a bit more heat-tolerant, I'd say.
