Hey - another possibility - it could be your fuel pump pushrod is worn down so it hardly pumps until the engine is running at higher-than-cranking rpms.. Just a suggestion.

There is an allen screw in the block under the fuel pump, pull it out and the fuel pump, then the pushrod drops out, check for length. I have a post about it somewhere here.

I had the same basic issue, really hard to start, excessive cranking after parked for a week, had to keep filling the bowls manually before starting.. and in hindsight I had intermittent fuel starvation too... The fix cost $16 and took 20 minutes.

But - I still refill the float bowl with a squeeze bottle so I don't have to crank the 20 seconds first. Now it fires up nicely and stays running.

Best,
- Art

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