Jiffy 2hp carb settings

[jj22]

I have a 2 hp 8" Jiffy. What are the best settings for the Tillotson carb on this engine? I can get my auger to run and drill ,but it doesn't run as well as it used to.
I use opti-2 oil and have my new plug gapped at .030.I see it has an idle adjustment screw, another large screw which I believe is the mixture adjustment and another small screw which is recessed in the carb body.
Is this the jet, or high speed adjustment?
Thanks for replies.

[Bob_D]

I'm not sure about the new Jiffys (New EPA standards). The older Jiffys have two screws. One is the idle jet and one is your high RPM jet. I use warm up my auger and adjust my low idle jet so the motor would idle just low enough so the bit would not turn. I dajusted the hight idle jet under load. I would have someone cut with the auger while I adjusted the idle screw. I found that it was much quicker for me to adjust it that way.