The Admin from... Nowhere!
So, I noticed tonight that my little 160 was coughing and farting and popping at WOT without the mower engaged.... So when I brought it back into the garage, I took it down to idle, and it died. Checked the idle speed screw on the carb, and it had loosened all the way out... So, I ran it back in until Littletractor was running at 1350 rpm (the recommended idle in the tech manual), then brought it up to WOT.... It STILL popped and coughed, so I backed it off to idle and diddled with the idle speed mix screw again. Ran it all the way out, then all the way back in, then out until I hit that sweet spot of higher RPM and smooth running (about 1550 RPM) and readjusted the idle speed screw back down to 1350... After that, when I ran it up to WOT, TOTALLY smooth, no pops or coughs at all.... Music to my ears! The question I have is, how often should you have to adjust the idle speed mix? I mean, obviously, you NEED to adjust it when things are running bad, but it seems mine drops out of adjustment over time... Anyone run into this on a regular basis? Do you think that having the idle speed screw shake out like that helped to misadjust my mixture?