Question on adjusting the L screw

[wendell]

My 7901 is running great but am having a small problem when restarting it. If I only shut it down for a few minutes in starts right back up with one easy pull. If it sits for about 15-20 minutes, though it is a real challenge. On the second or third pull, it will start but die out after a second and then it is a real bear. Sometimes, if I pull out the choke for one pull, I can get it to go on the second pull but last night, I flooded it out.

I am assuming I need to adjust the L, but not sure which way to go?

Thanks for your help.

 

[JasonBmac]

If your idle is reliable and stable, and your acceleration is brisk without bog or stumble, the Lo needle is set correctly, and you shouldn't mess with it.

15-20 minutes is getting into the grey area between "no choke" and "choked" starts....

If I'm re-starting my saw after that kind of break, I'll pull 3 x with no choke and fast idle.... If it doesn't start, I'll apply choke and start it as if cold.

What's happening for you is that the carb has a vapour bubble in it by the time you go to restart.... You start it and it runs for a second before the bubble starves it of fuel. If your saw has a half choke setting, that is a good way to deal with this, but modern saws tend to have the interlocked choke/hi idle dealeo going....

J