Jonsered 621 won't start

[blackberries]

I just rebuilt my Jonsered 621 and I'm having a hard time getting it to start. I replaced the piston, rings, crank bearings, and seals. The saw will only start if I put fuel directly into the carburetor. Once it's running it works perfectly and restarts easily when it's still warm. The saw ran great before I rebuilt it, so I am not sure what the issue could be. Do you think it could be a fuel delivery issue or something else?

 

[thornh1ll]

Sounds like a fuel delivery problem to me, check the impulse hose for leaks and giving the carb a full rebuild kit

 

[Marluxia_Assassin]

Kind of odd that it runs fine warm but not cold. Makes me wonder if there’s a small leak or restriction that’s just enough to starve it until the saw is pulling harder. Did you double-check routing of the impulse and fuel lines when you put it back together?

 

[Stihlqvarna]

Did you ever get it fixed?