Just a quick thing before you go disassembling the hole engine, as this might be a more common issue to this carburetor, with a simple solution.

Grab a couple of THESE and pop it under the throttle cam.

Like this:
[Linked Image]


I can't guarantee it will work, but this is a common fix, to a common problem, and is pretty cheap, it also might save you worrying about pulling the whole engine down.

Also, is there definitely some form of metal clip inserted on top of the diaphragm?

Cheers
Ty

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