The one-cylinder “M”, as designed by Pop Arnold, is the least expensive and easiest of the “M” series to build. With the exception of the base and connecting rod, which should be done on a milling machine, the engine can be built with an 11" lathe and drill press. The engine is rated at 5 hp, 600 rpm, with 150 lbs. of steam pressure.

The engine uses sealed ball bearings on the crankshaft and both ends of the connecting rod. The eccentrics are lubricated with Zerk fittings for grease, or can be fitted with oil cups.

A common “D” valve is used, which never needs adjustment for wear and is self-sealing. Reverse gear is of the Stephenson Link type, well known for its durability and cut-off control of the valving. The crankshaft is a straight piece of steel pressed into a steel crank disk. The cast iron cylinder has extra large steamways cast in, which gives the steam unrestricted flow in and out of the cylinder and accounts for this engine’s exceptional power for its size.

The M makes an excellent engine for a steamboat of 18' - 23' using an 18" propeller . We provide an adjusting knob on the reversing lever to set the cutoff at any point desired, instead of limiting the valve setting to a few notches on the quadrant.

The blueprints are offered for sale separately if you want to study the drawings first. Otherwise, the prints come with the kit. Prints are drawn full size and all dimensions are in inches and all threads are American. A machined reverse link is available for purchase separately. Ready to run price for the engine is $3,600.

As a final note, Live Steam Magazine ran a construction article on this engine featuring it on the cover of the January, 1990 issue.

Bore:    3"
Stroke:    4"
Shaft Size:    1"
Flywheel Diameter:    8"
Overall Height:    26"
Length Base:    9.5"
Width Base:    12.5"
Steam Inlet:    1/2" IP
Exhaust Pipe:    3/4" IP

Shipping Weight:    200 lbs.

We will try to arrange to ship this product by motor freight to save on shipping versus UPS ground. We will contact you to arrange shipping, and shipping charges will be added to your order only after we talk to you and have your approval.