Hit and Miss Engine

A Hit and Miss engine by Mick Cherry. I had the flywheels, main frame and base castings for a gas engine which I think they were from Bruce Engineering. I made these the starting point for the engine.

Having then decided the bore and stroke, I just did some loose sketches of what I wanted it to look like and then made it up as I went along. The engine does not have piston rings, it has a cast iron lapped bore and piston, they never wear out.

I spent a bit of time setting up, but that is what it is all about. It starts very well and just runs on and on until the tank is empty.

You will see there is some paint missing, but it has had a hard seasons work.

The spark plugs I use are from Hemingway Kits, they are Rimfire VR2 1/4x32TPI.

With regard to the ignition system, I use the good old fashion coil ignition. I go to a motor bike shop and buy a second hand 12volt coil, they are nice and small. Then I go to a back street motor car shop and buy the cheapest condenser I can, it′s no use going to Halfords as they only deal in electronic ignition, then power it up with a 6volt battery. You have to use 6volts as that′s what the plugs are rated at. But it works out OK.

I have had 3,000 rpm from the Anzani with no problem.

For fuel I use 9 parts petrol to 1 part WD40, this keeps any carbon deposit nice and soft, no trouble with valves not seating with the very soft springs I use for automatic valves.

Some people use one ignition set up and plug it into whatever engine they run. But I fit my engines with it′s own ignition, I know this works out dearer, but it makes for reliability.

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