Is the choke functional?

Accelerator pump may be helpful, but definately not necessary to start the engine if the choke is functional.

Doug, there are several different diaphragms used in the various YF Carters.

If the diaphragm is defective, engine will probably not run well, as fuel could syphon through the diaphragm.

But a rebuild may be useful.

Jon.


Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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