1" Bore x 1" Stroke Vertical I.C.

[kuhncw]

Kuhncw---That black thing on the end of the carburetor is a handle to turn in or out to richen or lean out the mixture flowing thru the carburetor.---Brian

Thank you, Brian.

Chuck

[Brian Rupnow]

THIS POST HAS BEEN TEMPORARILY REMOVED UNTIL I GET IT FIGURED OUT A BIT MORE.--APRIL 06-2021

[Art K]

So the cam timing is advanced to far? I had that experience the first time I got my Upshur single running. It wouldn't run more than about 1000 rpm's. It was advanced 3 teeth to much by the time I got that sorted out. When I went to far it ran awful.
Art

[Jasonb]

You could also back off the inlet pushrod adjuster a bit so the inlet does not open as soon due to increased lash. That way exhaust stays the same.

Does that commercial carb have an adjustable air bleed or similar? you should be able to adjust both mixtures to suit slow and fact running if it does.

[Bearcar1]

Or perhaps machine a new cam with a different profile. It could then be attached in and with the same attachment pin position as the original. I am most certain you will figure something out and it will be good.
 


BC1
Jim

[gbritnell]

I think what you mean to say is the intake is open too long in the compression stroke, not the power stroke.
gbritnell

[Brian Rupnow]

George--You may have caught me while I was undergoing a "stupid attack." The more I read thru the sequence of valve events, the more confusing it becomes. I can understand a puff of air coming out of the carburetor if the intake valve opens too soon on the exhaust stroke. I can't really see the intake valve being open at all on the compression stroke.---Brian

[Brian Rupnow]

I reset the cam timing by retarding the action of the cam by about 4 to 5 degrees. That made a tremendous difference to the way the engine idled and responded to the throttle being opened.
<a href="https://www.youtube.com/watch?v=LAPSzeWYGxs" target="_blank">http://www.youtube.com/watch?v=LAPSzeWYGxs</a>

[Admiral_dk]

Nice that you found a solution to the last bit too 

[crueby]

That looks and sounds absolutely terrific!

[Brian Rupnow]

Thanks fellows. ---I'm glad that it runs as well as it does, and I'm looking foreword to some "not machining" time.--Brian

[Art K]

Brian,
Glad to see you got the cam sorted out. It runs great. Now, take a well deserved break!
Art

[Bearcar1]

   yes but we are all still waiting to see the happy dance video....   


BC1
Jim

[Brian Rupnow]

[Brian Rupnow]

I have been asked about gaskets on this engine. There is a gasket 0.030" thick between the bottom of the cylinder and the crankcase. The head gasket is 0.030" thick. There is a gasket 0.015" thick between the two sides of the crankcase. These are simply standard utility grade gaskets, cut from rolls of automotive gasket material. Same material as would be used for fuel pumps, waterpumps, etcetera. I do not use a special grade of head gasket material anywhere on the engine.