Stuart "BB" engine

A vintage Stuart "BB" engine; an oversquare engine with fully enclosed crankcase designed for high speed running, it's ideally suited for direct coupling to a pump or generator. Fitted with enclosed ball bearing mains, balanced crank and hollow crankpin for lightness, Stuart tested the design for 4000rpm running at 70psi.

This one turns over freely and runs smoothly on 10psi of air - there is some wear in the big end, crankcase cover is missing some bolts.

Available from 1924 until 1941, these engines are becoming rather rare, particularly those complete with their original rear covers, many of which seem to get lost.

There is further information about the engine on Stuart's website here.