Slight misfire while idling

[CLStout]

Ariens 20hp 42" deck, model 936042. When idling, I can hear a slight misfire. It's fine at full throttle. New carburetor last summer, with new fuel pump and filter. New air filter and pre-filter. I didn't make any adjustments to the carb other than turn down the idle speed slightly.

Any ideas?

TIA!

 

[CLStout]

This is a Briggs and Stratton Intek 20hp v-twin engine, 2 bbl. Nikki carb.

 

[sgkent]

Ariens 20hp 42" deck, model 936042. When idling, I can hear a slight misfire. It's fine at full throttle. New carburetor last summer, with new fuel pump and filter. New air filter and pre-filter. I didn't make any adjustments to the carb other than turn down the idle speed slightly.

Any ideas?

TIA!

could be the mixture is off or there is a little vacuum leak, or a valve is not sealing properly. No one can crystal ball something like that over the Internet. You will have to do some troubleshooting and tuning to see if you can figure it out.

 

[CLStout]

Without looking at it, are there any adjustments for the mixture? I only remember the idle speed adjustment.
Thanks for your response, BTW.

 

[slomo]

Check for spark UNDER LOAD. Like this below. You can open the side screw out to increase the gap size, loading down the coil.