Is it possible to make a hot bulb Diesel engine from a petrol lawn mower engine?

Hot bulb engines were started by heating the bulb with a blowlamp, once running, combustion heat should cause the fuel to ignite next time around. Running on light load, that is often not enough, and the blowlamp needs to be applied.

The 2 stroke Bolinder engines used in canal boats were typical of this sort of operation.

The Drainage Museum, at Prickwillow in Cambridgeshire has a large two stroke twin cylinder which needs a blow lamp applied to each cylinder for starting and early running. Once warmed through, it is self sustaining.

The WaterWorks Museum in Hereford, has a Campbell gas engine which requires constant application of heat to the hot tube to keep it running off load.

A normal four stroke carburetted petrol engine, if the compression ratio is fairly high, will run on, (very roughly) for a while, after the ignition is switched off, if the ignition timing is too retarded. The easy way of stopping, was to open the throttle wide, and admit a lot of cool air.

I would have thought that a side valve engine, with a hot bulb would be have so much dead volume as to be unlikely to have a high enough compression ratio to run without application of external heat.

On the subject of engines running away on their own oil, or accumulated fuel; it is not an experience you would want to choose deliberately! Even if you expect it, the rate at which they accelerate is incredible.

Howard

Now he tells me - I used to crash into fourth with the handbrake on

Neil