After a protracted negotiation by e-mail, I dropped into Aylesbury on the way back from Kent on Monday evening & carried off a complete & genuine Johnson manufactured Iron Horse, another without the wire frame made by the Outboard Motor Corp of Canada & a very nice little Onan. All are 12 volt 300 Watt, WW2 devices (although the Onan might yet turn out to be 24 Volt).
I was pleasantly surprised to be presented with several boxes of manuals and brochures. These I've sorted into stuff I want & stuff to pass on. Also a box of "Old Glories" and "Vintage Transport" which don't interest me. If anyone wants them, say so OFF LIST & I'll bring them to Enstone.
It was ages since I'd got my hands dirty, but I spent a chunk of Tuesday getting the Johnson Ferrous Nag going. After stripping the carb, removing the flywheel & cleaning the points, all seemed fine but still nothing doing. A thumb on the plug 'ole revealed no compression at all - what had felt like compression was actually the flywheel binding on the magnet pole piece which subsequently fixed itself.
I took the head off & the exhaust valve was well and truly stuck open, but a squidge of Plus Gas into the gaping port and tapping it back on its seat a few times soon fixed it. I was surprised to see there was no head gasket but the faces were very smooth & clean, so I just Hylomared the joint and nipped up the bolts evenly but not too hard. A blessed electric start version, when reassembled it fired up easily & ran well. The mixture screw makes a big difference on these small bore direct lift carbs & getting it right means the difference between a start and not a splutter. Once correct, I find they are an easy starter.
regards,
Kim Siddorn