Live Steam 
Twin Cylinder "Marine" Model Steam Engine
Duplex Version 
Fully Machined Kit in Brass, Bronze and Steel 


The vertical duplex twin cylinder "marine" engine is two single cylinder marine engines connected via a large flywheel on a steel plate, top brace plate and (optional) inlet manifolds.

As with our other marine engines a 15mm shorter version is also available.

As such it is still relatively simple and retains the basic mechanics of engines which powered ships and larger boats which needed the extra power provided by a twin cylinder engine.

NOTE: Pictures are of the assembled kit, this listing is for the kit of parts. Also shown is the optional manifold.

This marine engine layout has two double acting cylinders, eccentric driven piston valves and the large brass flywheel offers smooth running and is capable of powering a range of accessories, in a variety of roles. The engine also includes 2 x double split bronze pedestal bearings for the crank shaft, tube sliders and a substantial cast base.

On the two half crank shafts, the cranks for each cylinder are offset by 90° which means the engine will self-start in any position.

The engine will run in reverse by applying the steam (or air) input to the outlet ports. Our Reversing/Throttle Valve (optional extra) will control the direction and speed of the engine in either direction.

The kit consists of precision produced parts each carefully made and checked to ensure ease of assembly and reliability in service.

The cylinder assembly and piston are manufactured from brass and the piston shaft, connecting rods, column screws and valves from stainless steel so are not susceptible to corrosion. The piston shafts passes through an adjustable glands and the steam inlet can be either side of the chests.

There is also a 15mm shorter version of this engine based on the short marine single.

Detail Specification:
- Type: Tube Slider
- Bore: 14mm
- Stroke: 18mm
- Flywheel Diameter: 70mm
- Valve type: Piston
- Height (excluding manifold): 160mm
- Length: 160mm
- Width: 75 mm
- Weight: 2.2Kg
- Connections: 1/4" x 40 tpi ME

The kit consists of a set of fully machined parts that can easily be assembled using simple tools such as a screw driver, allen keys, pliers and metal file. The parts are mainly unfinished metal and will also require painting, polishing, filing, etc.

NOTE: The kit is supplied with socket or hex head set screws, although some screws for ease of installation, have to be socket head screws. Some screws as provided may need to the cut or filed to length to complete the model, contact us if this will cause a problem.

When assembled the engine is fully working and can be run using steam or simply using compressed air e.g. from hand or foot pumps.

To power the engine with live steam, connect it to one of our Model Steam Boilers.

NOTE: The model steam engines and boilers are NOT children’s toys and should not be assembled or operated by children unless under close supervision of an adult.

Vertical Marine Twin Cylinder Engine Kit - Duplex Version

  • Product Code:VTAL
  • Availability:1
  • £340.00


Available Options


Related Products

4mm 5.5mm Spanner for M2 and M3

4mm 5.5mm Spanner for M2 and M3

Small stamped steel spanner for use with M2 and M3 hex head screws/nuts.A basic tool for assembling ..

£1.00

Steam Reversing Throttle Valve

Steam Reversing Throttle Valve

The valve will allow our engines  to be run in forward and reverse and their speed controlled b..

£49.00

Small Adjustable Displacement Lubricator for Live Steam Model Engines

Small Adjustable Displacement Lubricator for Live Steam Model Engines

Small solid brass adjustable displacement lubricator/oiler - should be installed in the steam pipe f..

£42.00

Large Adjustable Displacement Lubricator for Live Steam Model Engines

Large Adjustable Displacement Lubricator for Live Steam Model Engines

The Large Adjustable Displacement Lubricator/oiler is made mainly of solid brass and should be insta..

£46.00

Medium Adjustable Displacement Lubricator for Live Steam Model Engines

Medium Adjustable Displacement Lubricator for Live Steam Model Engines

The Medium Adjustable Displacement Lubricator/oiler is made mainly of solid brass and should be inst..

£45.00

Tags: Live Steam, Model Steam Engine, Fully Machined Kit, Twin Cylinder Marine Engine