E: Engine How critical are the rear cylinder oil feeds!

vibrac

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I needed to reread this thread as I have a special engine where the oil hole in the crankcase side will never feed the piston correctly I note that while the term 'blocking off' occurs a number of times nobody has specified the best way to do it my barrels have not had the oil hole drilled is that sufficient? I would rather have the oil on the cam than perhaps funneling back to the crankcase in the annular gap twixt cylinder and case
 

vibrac

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I must be wrong:oops: I thought the feed up that spindle also lubricated the camshaft bushes etc as well as the cylinder bore hole
 

Bill Thomas

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It must make a bit more pressure to the cams etc by blocking the follower spindle.
Not sure I can bring myself to do it, But it might be more easy, That hole never seems to line up !, At the right place below the rings. Cheers Bill.
 

davidd

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Oil Diagram.jpg

This is for the twin. The only item that may be hard to picture is the "recess". That is the chamber in the back of the cases where the oil goes after it is scraped off the flywheels.

The Comet is a little different. Only two oil feeds on the Comet. One to the camshaft and the cylinder wall is fed by the intake cam follower spindle.

I think Greg's method with a shim is probably the best. There is nothing that can come adrift to circulate in the oil system. Presumably, any additional oil running above the jet would be available to go to the cam. It is difficult to know how much that would be. The supply seems more abundant, but it is flowing through the same size hole.

David
 
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