I have always wanted an engine that will run on the smell of an oily rag and this will be the closest I will be able to get to reach my goal.
The Lister or Listeroid 6/1 is a great engine to run continuously as a battery bank charger in an off-grid situation where the house and shop loads can then run off inverters. Trouble is the 6/1 is a large displacement engine, nearly 1.5 litres displacement. Anyway you run it, it has to use enough fuel to keep warm and not wet stack. I wanted a smaller displacement engine that could live on considerably less fuel that was also capable of operating at Lister CS speeds to get low noise operation and long life. No such engines seem to be available on the marketplace so I thought I might be able to `make my own` so to speak.
I have just fabricated a very strong and heavy welded steel frame to maintain the precise geometry between a small China JD175A diesel (353cc horizontal water cooled single rated at 6 HP@2600 RPM) to a 180 pound flywheel directly coupled to the original flywheel on an outboard bearing shaft. The flywheel I am adding came from a agricultural hay bailer and is a very high quality casting and is very well balanced. It is a stover type solid disc center with three large holes and an outer rim width of 5 inches. The diameter is 19-1/2 inches. According to the 60 MPH rim speed rule for cast iron wheels this flywheel should be safe to run at 1000 RPM max. At 1000 RPM my JD 175 should be capable of making about 2+ HP. That can translate into a KW or slightly more in electrical output. In 24 hours I can put 24 kWH into my battery bank, A house can run on 24 kW hours in a day.
I am retaining the original flywheel on the JiangDong 175 engine and have manufactured a coupler that bolts up to the JD the same way the V-belt pulley gets installed with three bolts at 120 degree centers. My coupler transfers rotaional energy to the large flywheel through three coaxial rubber damped couplers. This is tight coupling but provides damping so that harmonics cannot build up in the JD crankshaft nor is it likely to suffer cracking from high peak shock loading. At least that is the idea.
My large flywheel has it`s own jackshaft and two ball bearings to bear the static weight of the massive flywheel. The center `pin` of the coupler half that is bolted to the JD flywheel terminates in a bronze bushing in the center of the large flywheel. This provides some mass support of the large flywheel to the engine crank in the radial direction.
Today I finally got the engine and big flywheel all mated up on the new frame in near perfect alignment for the first time. I fired it up and ran it for about 20 minutes. The stock governor on the JD would shut off the fuel rack completely trying to run slower than about 480 RPM, so that is where I let it run. There is no vibration at all and a glass of water has almost no ripple on the surface when perched on the frame base in three corners. In the forth corner it has a slight ripple pattern. I have not yet fine tuned the alignment between the engine and large flywheel with shims. I can see that I need to add about ten thou worth of shimstock behind just one of the three perches that hold my coupler to the JD flywheel, that`s it!
At 1000 RPM and full power I expect to be able to run about 3 hours making 1 kW electric output on just a litre of fuel. It appears that this plant will run at 500 RPM, so 500 watts could be possible at a real slow speed. At 500 watts, 6 hours per litre of fuel use ought to be possible. That means it may run a 24 hour day on just one gallon of juice. Only testing will verify if this project will succeed but so far my experimantal plant appears to run OK.
Now I need to add the framing necessary to mount the big DC generator I plan to use and see how it performs under a load. If OK I`ll install the fuel tank and radiator system.
I need to get into the stock governor and modify it to work over the new slower speed range. I expect to have to increase the mass of the flying weights.
I`ll post pics as soon as I am able.
edit to correct minor tech detail.