The above post about the diaphram being stiff may indeed be the case - especially if it was run with synthetic oil and then put in storage. Synthetic oils will degrade the rubber over time. I have used only the standard 2-cycle oil you find at any hardware store, mixed according to the instructions (usually 25 or 32:1). My Q-35 sat in the shed for 10 years. I pulled it out 2 weeks ago, changed all the fuel lines out, filled up the tank, and after priming until she 'popped', opened the choke - and started right up where she left off. Those carbs (and engines) are sturdy and reliable - even if abused. Not saying that's the case - but I doubt it's the innards of the carb. I could be wrong - would not be the first time!