Above: flywheel side view

Above: water pump side view
Below: water pump side with cooling system installed

ENGINE NO. TEN DATA

Cylinders: 1
Type: Single cylinder
Bore: 0.943 "
Stroke: 1.0 "
Displacement: .698 cu in
Compression Ratio: 7.9:1
Ignition: Glow plug
Cooling: Automotive coolant
Fuel: 15% nitromethane/methanol mix
Est. Max. RPM: ____
Est. Horsepower: ___

BUILDER'S NOTES

Background -- This is a model of an old T-head engine which was popular around the early 20th century, mostly for small fishing boats and stationary purposes. The model is smilier to one designed by Hamilton Upshur in Model Engine Builder Magazine, Vol.1, issue 3. Of course I couldn't leave the design alone and had to make some changes. I used ball bearings, a timing belt for the camshaft drive in place of the gears. I used a split connecting rod bearing so I could use bronze inserts on the crank. Since it is a liquid cooled engine and couldn't run long without coolant, I had to build a radiator, which of course required a pump on the output shaft. Isn't that how it goes?

Construction -- In general, I followed the Upshur design: plates were bolted together to make a crankcase and the cylinder was one piece with the head bolted in place. Note that I didn't use a two piece head for cooling but used fins. It seems to be adequate. Valve timing was set up with the exhaust BBDC lead time (around 40 degrees) of crankshaft angle. Intake cam lags exhaust by 110 degrees. Note this cam is set in reference to the exhaust cam and not crankshaft rotation. If the exhaust timing is changed it's imperative that the intake timing be reset to maintain the 110 deg. difference between intake and exhaust cams.

Operation -- The engine starts easily, is a delight run and is suprisingly quiet with a simple straight through muffler design.