Vertical Steam Pumps

3 Vertical Steam Driven Boiler Feed Pumps

In these three pumps the layout is the same, having the steam cylinder at the top and the water at the bottom, all working on the same principle. In the steam chest there are two slide valves, the first one operated from the piston rod which passes steam to a shuttle. This shuttle has the second valve attached to it and controls the steam in and out of the cylinder. This is a reliable method of operating the pumps and is self starting from any position. They can be run at a fairly high speed, or slowed down ‘till barely moving. They are all suitable for either steam boats, locomotives and stationary steam plants. On the first sheet of the drawings there is an assembly with all parts itemized along with a parts list.   The other sheet or sheets shows details of all the parts to be made.

12 inch pump

12 inch Vertical Steam Pump

12 inch Vertical Steam Pump

This pump has been designed for full size steam boats and similar applications. The water end is divided into two main castings, the cylinder and valve chamber. This makes for ease of machining, also the water ways are drilled which ensures correct position, size and no sand inclusions. The bosses are big enough to take ½ inch BSP fittings. The valve chamber top cover with the water outlet can be fitted, at the construction stage, either way. Also with the cover removed all four valves can be taken out for inspection.


Height 11.5 inches Steam Cylinder 1.5 inches dia.
Width 4 inches – less fittings Water Cylinder 1 inch dia.
Depth 5 inches – less fittings Stroke 2 inches

Approximate built up weight 12lbs.

Parts supplied:-  Drawings, 6 O-rings, 13 Castings – the steam cylinder, valve chest and cover castings can be supplied in a choice of iron or gun metal at no extra cost.  2 x 2 BA hex brass set screws and nuts.


6 Inch Pump

6 inch Vertical Steam Pump

6 inch Vertical Steam Pump

Similar in principle to the above. The water cylinder and valve chest are one piece. All castings supplied are in gun-metal. The drawings show alternative water valves i.e. ball and the more efficient three wing type.

Height 5.625 inches Steam cylinder 0.75 inch
Width 2 inches – less fittings Water cylinder 0.5 inch
Depth 2 inches – less fittings Stroke 1 inch


Parts supplied:- Drawings,    7 gun-metal castings,     6 O-rings for glands & pistons.

3 inch Pump

3 inch Vertical Steam Pump

3 inch Vertical Steam Pump

Due to its size this pump is different from the other two. We have done away with the pivoted valve operating arm and in its place milled cross ports have been employed.   The ram of the water cylinder is an extension of the steam piston rod. The other difference is that it is single acting and the two water valves are horizontal. Because of this the two 3 wing valves are kept on their seats by springs.

The pump can also be used as an oil pump. If so the ram at the pump end should be reduced to .187 or .125 inch diameter.

Height 3.1 inches Steam cylinder 0.5 inch dia.
Width 1.1 inches – over fittings Water cylinder 0.25 inch dia.
Depth 1.375 inches           Stroke 0.625 inches

Parts supplied:-  Drawings,   3 O-rings,   2 springs,   6 gun-metal    castings (from one, 3 items are produced).

Below is a short video of  this engine in a 3 1/2″ Locomotive application: