Senior project

[Chippie]

Today, attention turned to some fiddly jobs….
The crank bearing caps needed drilling and tapping for the oil dash pots, the cam timing gear needed a couple of holes, one of which is to locate the cam, which is now pinned to the gear.
The cylinder has been honed to accept the piston, with a final polish with some T cut, although the bore doesn’t need to have a mirror finish, in fact a slightly roughened surface is required to retain the oil that lubricates the bore/piston skirt.
Some photos showing how assembly is going….

 

[Blobber]

Looking great, Its a fair bit bigger than I was expecting!

 

[chrismac]

cracking engine, are you going to run it off a buzz coil ?

 

[Chippie]

Looking great, Its a fair bit bigger than I was expecting!

The flywheels are approx 10” in diameter, bore is around 1-1/2”, stroke is 3”..it’s a fair bit of weight to lug around now…

 

[Chippie]

cracking engine, are you going to run it off a buzz coil ?

The switching arrangement for ignition is pretty basic, there’s a copper stud on the cam gear, and a mating rivet attached to a spring steel strip mounted behind the cam gear..their recommended ignition system is for a trembler coil system, given the low compression of the engine…

With the piston at tdc, there’s quite a space above it before the cylinder head is attached, so I’m guessing it’s quite low, but makes for an engine to run off various types of fuel…petrol, gas….etc.

But to answer your question, I haven’t decided…

Most of my time has been spent on machining all the parts necessary to build, once completed and assembled, proven by running, I’ll spend time on cleaning up the rough castings, blending areas where necessary and then it will be painted, not sure on colour yet…