I was very kindly given a Tillotson carb kit along with a printout of a McCulloch Flatback shop manual by Jeff today, thank you sir!
so I'm looking through the pages and what's this?? A rubber one-way duck valve in the impulse passage? If this is located somewhere inside my Mac Flatback carb, it is almost certainly hardened up and my guess is not allowing the crankcase pulses to make the carb function properly....
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Sorry about that thought maybe book would help
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