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Webster build issues

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John Rudd:
I have restarted the Webster build after a long spell.....
Got to the stage of making the rocker arm for the exhaust valve.....
Having measured and made all the necessary bits, I find that the centre of the bolt that operates the valve does not sit directly under the valve!
I made the spacer as described but the rocker doesnt sit right..... :scratch:
Anyone else have this problem? Have I done something wrong ?

cwelkie:
The (Webster) drawing (on page 8) isn't as clear as it could be ... there is an offset to the valve end of the rocker.  Even though each end is dimensioned at 0.25" wide, there is a 0.063" offset which means starting with 5/16" wide stock and most of it back along one side.

... then again that may not be what's going on here.
Charlie

John Rudd:
Charlie,
Looks like I made a skoolboy error......
I started out with 1/4 sq stock and looking at the draŵing and how my bits fit, I think that is is the issue.....more scrap for the bin :dremel:

So start with another bit.....

John Rudd:
So how is the cam for the exhaust valve made?

I dont see it as a simple offset turning exercise?

DavidA:
I do recall that on a lot of early engines the cam follower was slightly offset to the valve stem to allow the valve to rotate a bit with each operation. This allowed for more even seating of the valve on the seat.

I don't know if this is related to your problem or not.

Dave.

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