Chenery Aero V-twin 4stroke

I am about to start on machining the Hemingway Kit castings, etc for this engine and wonder if anyone out there who has made/is making same , would be interested in sharing experiences.

Hi Gray,

Thanks for your information. At the moment I am at the planning stage ,trying to absorb all the information I can find.One area that seems somewhat vague at the moment is cam design and timing, In fact ,on the drawings I have a major dimention is missing and I wonder if other builders have worked this out in different ways, hence timing problems. I intend to run this as a Glow engine.The Chenery notes I have state that valve timing is far less critical with a glow engine. Is this your experience? Another point I would like to solve is the one of lubrication. The drawings state"Oil is drawn from resevoir by crankcase depression" Presumably the resevoir is a seperate unit. Is this necessary with glow fuel? I notice that the twin carb engine in your photo has what looks like a screw down lubricator on the crankshadt bearing This is the point where oil enters ,as shown on drawing.

Regards,

Keith

Hi Grey,

Presumably the 10cc of oil gets through to the timing gears and camshaft? With a typical glow fuel with 20% castor oil, does that dilute the sump oil?

I had a similar problem with the conrod fouling slightly,on a Sperry 5cc Diesel, and I cured that with some local scraping.

I will look up the site of the cam machining right away.

Keith

Hi Gray,

I have printed the cam machining information. Are the dimentions of the cams correct for the V-twin as originaly drawn, or are they after your mods?

My supplied gears are both metal, Steel for the camshaft and brass/bronze? for the crankshaft. I imagine tufnol will be somewhat quieter, but I will cross that hurdle later.

Keith

The glow fuel won't lubricate the bottom end as it is not drawn through the crankcase like it is on a 2-stroke glow engine and should not mix with the crankcase oil unless you have leaky rings.

Hi Jason

Thanks for that . The jigsaw puzzle is gradually taking shape!

Keith

Hi Grey,

I am getting along with machining parts and query whether the oil ways drilled into the crankshaft are only necessary if a pumped lubrication system is used,as hinted at In Chenerys build notes. Your friend, Johns engine has a reservoir on the front bearing.Does the drilling for this only go through the ph bronze bush?

Also where are you filling the 10 cc of oil into the sump from and draining it?

Keith

Hi Grey,

I think I was hoping you would say you had not drilled out the crankshaft,etc as plenty of oil would be thrown around for the big ends with the 10cc fill, as you had no success with the suction method.

.I have also decided to make a deeper sump plate, probably with a fill/drain plug.

Keith