and it seemed to work OK when I started the engine in the workshop...
but when I'd installed the engine in the hovercraft, adding the drive belt, top bearing and fan, it must have
placed more weight/strain on the bakelite pulley and it cracked right across after just three or four pulls.
As it's at least 20 years old I can't see I'll get a replacement so I've measured all the dimensions
and I'm starting to fabricate a new one in mild steel...
Here's the original bakelite wheel...it was a bit poorly before it cracked right across! The centre part with the two pivots is 58mm (about 2 inches) across.
So I cut a 135mm disc out of 3mm mild steel plate, drilled a hole and filed it out to 17.5mm. Then I cut a 20mm ring off the outside edge...
After welding the ring to the middle bit with a 3mm 'step' I cut a 10mm x 300mm x 1mm mild steel vertical 'spacer' and welded it in place...
Then I cut another ring in 1mm mild steel and welded it in place to form the 'wheel' for the pull-start cord. Here I've added some of the 'internal' components for the 'turret'.
I cut various bits of metal to make the 'turret'...and recovered the brass spacer & bob-weight pivots from the original wheel (as they're an odd size, 7.9mm).
The 'top' plate with the bob-weight pivots in place.
Position/spacing is critical in this piece so I spot welded everything together to test. It worked OK, the pivot points are less than 1mm out, close enough!
Final assembly...all mild steel painted with Kurust to stop it rusting (colours it black/purple), recoil spring oiled & a smear of grease on each bob-weight & return spring, etc.