I've been given a number of diesel engines (and me an electric-head

The cylinder head is 18.5mm dia and from pics I've seen online, it would be missing a machined fuel tank at the back and perhaps a spring start at the front (there are wear marks on the black anodising of the crankcase behind the prop driver Mr Holmes). The rear of the crankcase has a single central tapped hole around M2 - I'm assuming some awful BA thread like 10BA - I gave up imperialist measurements as a child around 60 yrs ago - it still seems to linger on - and on

TIA
Cheers
Neil