I had a twin cylinder air cooled electric start Petter hooked up to a 10KVA 240v alternator as an auxiliary power plant that ran pretty fast revs but did not belch much black or blue smoke except when I had the 3Phase power operating off it and then under load the smoke increased along with diesel consumption.
It was a good unit all self contained in a cradle along with the fuel tank.
I sold it with the property when I left the Atherton Tablelands in North Queensland 12 years ago.
I had a lot of Southern Cross Stationary engines up there mostly BDC and YBs. Sold them all as too large to shift.
Matter of fact in my toolbox I have a Knurled tube for decompression operating, off a YB Southern Cross if any one is interested in one.
I believe they are like hens teeth to find.
Cheers,
Grasshopper Max