On 5/25/2011 7:55 AM, Jules Richardson wrote:
....

Yeah, it's getting pretty bad on both the old B+S engines that I have,
which are around 25 years old now. They use tiny grub screws to hold the
throttle stop onto the shaft too, and there's no chance of getting those
out after so many years - removing the stop is the only way of removing
the shaft.

Maybe I'll motivate myself to cut the stop off one sometime (and make
myself a replacement) if I can plan a way of adding bushes to the carb
body (which I expect is what's worn; the shaft's probably not too bad)
....

It's pretty trivial to grind off the throttle plate screws then remove
them and replace. I've done that in trying to cobble up a fake bushing
w/ some shim stock and other halfbaked goes at it.

The trick is the machining for bushing in the carb body to accurately
bush the shaft. I've wondered if one of the JB Weld or similar products
would be hard enough but figured unlikely so haven't ever tried it. It
wouldn't be bad if one had a milling machine setup (or very, very good
drill press, even) but my press is ok for farm repair heavy stuff but
not up to the task for such precise work. The guy in town wants way
more than they're worth for setup charges.

Indeed, it is the carb body casting that wears; I've mic'ed the shaft on
a couple and they're barely discernible as to wear--it's all in hogging
out the body from the longterm vibration.

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