This was Mamod's first expansion into mobile steam engines in 1961, and created a turning point in the history of the company. It was a good looking little engine which has changed surprisingly little in general appearance to the present day (the main changes being a different style of rolls and a reversible engine).
It is held together entirely with nuts and bolds, with the exception of the burner, which is attached to the scuttle with a single rivet. The rolls are cast aluminium and are held in place by plane domed hub caps.
The vapourising meths burner is permanently attached to the scuttle. It, therefore, has no handle which, in later versions, served as a towing hook. The boiler is 4 7/8" long by 1 3/4" diameter, embedded in the firebox at the rear end and bolted to the smokebox at the front end. The front of the smoke box sports the legend Mamod Birmingham England. A safety valve is mounted near the front of the boiler, an all brass whistle over the firebox and an overflow plug (with a single ended "tommy bar") at the rear end.
Steam is fed directly to the engine, which is a single cylinder, single acting, non-reversing type, identical to that on the MM2 of the time. It's dimensions are 5/16" diameter x 3/4" stroke. The crankshaft is the smaller 1/8" diameter. Drive is directly from the flywheel to one of the rear rolls via a spring band.
As received, there was some rust around the firebox. I removed the rust and touched up the paint. The paint elsewhere on the engine is chipped but otherwise not too bad.