Enya 46-4C 7.5cc Four-Stroke Glow R/C Aircraft Engine – Japan SECOND HAND - manifold welded to cylinder head valves stuck (Box 161)

Vintage Enya 46-4C four-stroke glow engine, manufactured in Japan by Enya Metal Products Co. Ltd. This is the classic single-cylinder 7.5cc (.46 cu in) pushrod-operated OHV four-stroke, introduced in 1984 and tested in Model Aircraft News in November of that year. It was regarded as a particularly high-performance four-stroke for its size at the time.

The engine uses a single cylinder, pushrod-operated overhead-valve layout, twin camshafts supported in bronze bearings and a two-ball-bearing crankshaft. Displacement is 7.499cc (0.4576 cu in), with a 22.3mm bore and 19.2mm stroke and a measured compression ratio of approximately 7.8:1.

Period testing recorded a net output of approximately 0.72 bhp at 13,200 rpm, with 65 oz-in of net torque at 9,000 rpm. With the standard muffler, documented propeller combinations included 12×6, 12×5, 11×6, 10×7 and 10×6, with the smaller propellers allowing the engine to reach higher rpm.

The 46-4C was an important Enya design of the mid-1980s, featuring enclosed valve gear, a more sophisticated carburettor incorporating a choke control and its own muffler. A later Mk.II version was subsequently produced with a strengthened front end; this example is being identified as the original 46-4C rather than assuming it is a Mk.II.

Specifications:

• Manufacturer: Enya Metal Products Co. Ltd., Japan
• Model: Enya 46-4C
• Type: Single-cylinder four-stroke glow
• Displacement: 7.499cc / .4576 cu in
• Bore: 22.3mm
• Stroke: 19.2mm
• Configuration: Pushrod OHV
• Twin camshafts
• Two ball-bearing crankshaft
• Compression ratio: approximately 7.8:1
• Period tested power: 0.72 bhp @ 13,200 rpm
• Approximate period weight: 410g with muffler
• Typical propellers: approximately 10×6 to 12×6
• Fuel: Methanol-based glow fuel
• Country of manufacture: Japan
• Introduced: 1984

This is a used vintage engine showing age-related cosmetic wear, manifold welded to cylinder head, valves are stuck staining and surface oxidation consistent with its age. The engine turns over freely. It has not been tested running, so the condition of the compression, bearings, carburettor and valve train under operating conditions cannot be guaranteed. The fuel system, glow plug and general mechanical condition should be checked before attempting to run.

A desirable vintage Enya four-stroke suitable for a period R/C aircraft, restoration project, engine collection or vintage model-engine display.

Manufacturer: Enya Metal Products Co. Ltd., Japan
Model: Enya 46-4C
Type: Single-cylinder four-stroke glow
Displacement: 7.499cc / .4576 cu in
Bore: 22.3mm
Stroke: 19.2mm
Configuration: Pushrod OHV
Twin camshafts
Two ball-bearing crankshaft
Compression ratio: approximately 7.8:1
Period tested power: 0.72 bhp @ 13,200 rpm
Approximate period weight: 410g with muffler
Typical propellers: approximately 10×6 to 12×6
Fuel: Methanol-based glow fuel
Country of manufacture: Japan
Introduced: 1984