I got my first model engine running which is currently under the single, horizontal engine section of the gallery called the Peasant.
I finally got my Peasant engine running on April. 25/ 08 at 7:00 pm. When I first attempted to start it that morning, I wasn't getting it to fire now matter what. My carburetor was also hard to regulate and flooded the engine way to easily. Even without the carb, it wasn't firing even with starting fluid. I had good spark, I thought there was adequate compression so at the moment I figured that the spark plug was located too far out of the combustion chamber. After I recessed it further in, it fired and revved up once on starting fluid. Now, carburetion was the problem, so I made a new carb with a long gradual taper on the needle. After this the engine would fire consistently but not run. Even though it still revved up before on either, I figured that compression was too low. Luckily I found a plastic o-ring injector seal from a surplus Cat 3208 engine gasket kit laying around the shop. This fit perfectly in the bore of the cylinder block. I machined a groove in the piston, split the ring and inserted it. Now the engine had lots of compression and immediately ran for a few seconds. I still have to oil the piston quite often in order to keep compression and lubrication up. We clocked it at about 3000 - 3300 rpm. The engine needs lots of tidying up and remaking of some parts to finish it but otherwise it is a lot of fun for the first time.
It runs very well on straight gasoline and a rough mix of wd-40.
The bore is about 5/8 and the stroke is 9/16
For ignition I used a 12 volt automotive coil, 12 volt battery and some Delco points and condenser from an old John Deere distributor. The plug is a rimfire 1/4 -32 which I purchased over the internet.
The valve seats I made directly in the cylinder head with a small center drill and the valves from nails. The springs are from a "clicker" pen, The retainers and keepers are from modified pop rivets and pieces of wire.
I put ball bearings from old hydro meters in the connecting rod and crankshaft which spins very easily.
The cam lobes I made with a file and silver soldered them onto the shaft.
The pushrods / lifters are just gas welding rod with a small nut welded at one end and ground smooth.
The carb and rocker arms are made of key stock.
The fuel tank is an acrylic paint container and the fuel line is the insulation from a piece of wire.
Most of the parts on this engine are made from scrap parts laying around the shop. The only expense was the spark plug and a sherline mill / lathe that I bought / got for Christmas.
This is my first attempt at a model gas engine. I call it the "Pesent" because it is made almost entirely of scrap metal laying around the shop and has very little money invested. I am not to good with plans and drawings so the entire project is my own design out of my head. it is roughly 9/16 bore X 5/8 stroke. It has no head gasket, i just lapped both surfaces, add some grease etc and so far it seals perfectly. The crank and connecting rod are suspended by bearings form old hydro meters. The camshaft lobes, I made form some round spacers, and bolted them in a homemade fixture and filed them to size then polished them. This is what I call the "Poor mans camshaft grinder",,, oh well ,, it works for me. The gears are from a mechano set. The valves are made form nails that i turned down and so far they hold good compression. I still have quite a few things to finish and hopefully it will run. I will try it anyways,,,, but so far I think that the aluminum flywheel is too light.
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