Bench Running a Small Glow Plug Engine

Thought I would take you through bench running a small glow plug engine. This is quite easy to do, you just need to follow some simple steps and you will be ready to go. Bench running is a good way to get used to starting and tuning these small engines. Even model car engines can be run on the bench with a propeller. This way you can learn in a controlled environment.

The video takes you through the stages of mounting it, fuel tank, plumbing, propeller and throttle.

As this shows a small four-stroke engine then this needs a “hot” glow plug, otherwise it is likely to cool down between combustion strokes. The fuel has 16% nitromethane, this is quite high for a stock fuel, but again this will make starting and running easier.

OS FS-20 Specification

  • Single-cylinder glow-plug ignition four-stroke
  • Overhead pushrod operated valves
  • Barrell type carburetor with choke
  • Bore = 18.0mm
  • Stroke = 14.0mm
  • Displacement 3.563cc (0.2174cu in.)
  • Compression ratio 7.2:1
  • Weight 263g
  • Power = 0.31bhp @ 12,500rpm

This little engine is no longer in production. You can buy them secondhand and this example has been run before, but appears to have had limited use.

I changed the original plug for a new hot plug and after some priming it fired up very easily.

Care Points

Bench running a small glow plug engine is quite easy, but you do need to just be careful and fully aware of the engine and what is happening around it.

  • Never stand in line with a propeller
  • Never reach over the propeller
  • Wear a tough glove when starting by hand
    • If the propeller stops or the engine back fires I can guarantee it will hurt
  • Never start or stop the engine using a stick on the propeller – this will cause damage and the propeller is likely to break later if not immediately.
  • Ensure no loose clothing can fall into the propeller
  • Make sure the engine and stand are secure

wright 9 cylinder radial

Ken-ichi Tsuzuki Model Engines

Ken-ichi Tsuzuki Model Engines took my breath away. I came across his website by chance and have spent ages going through his work. This page will hopefully introduce you to Ken’s work and be a starting point to explore more. I asked Ken why he makes model engines…..

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