MS280 leans out after cut..

[Drew4522]

Been toying around with an MS280 I got from a friend. Runs "ok".. starts and idles rough. Revs fine but when I let off the throttle it jumps and skips around and does not smoothly and quickly drop down to idle. Went through the normal gamut of troubleshooting, cleaned and rebuilt carb with Stihl parts, replaced fuel and impulse line, and replaced intake manifold boot. Carb is adjusted to factory settings. Muffler is mildly opened and screen removed.

It definitely leans out but I just for the love of all things Holy I cant figure out where or why. Has almost 160lbs comp..what am I missing..?

 

[Westboastfaller]

sounds like it fluttering down. any change when you move the carb around? spring on the carb? manually use you finger to press it back. maybe the carb needs a serious soak?

 

[Drew4522]

Serious soak is my next step. Saw did not run when I got it, impulse line was cracked..which was a project in itself on this particular model...

 

[Chainsaw Jim]

The factory setting is basic and meant as a starting point to keep it running long enough to warm up for tuning.
The metering lever in the carb is likely set too high, but first try backing the low side screw out a wee bit to see if it eliminates the problem. Having it set too lean will cause it to come out of the cut that way.
I just tuned an 044 that says 1/4 turn on the low. Once it started warming up it quit running until I backed it out about another half turn.

 

[Drew4522]

The factory setting is basic and meant as a starting point to keep it running long enough to warm up for tuning.
The metering lever in the carb is likely set too high, but first try backing the low side screw out a wee bit to see if it eliminates the problem. Having it set too lean will cause it to come out of the cut that way.
I just tuned an 044 that says 1/4 turn on the low. Once it started warming up it quit running until I backed it out about another half turn.

I've richened it on both screws to the point it wont start or run..same symptoms tho. Going to pull the boot off and make sure I didnt damage it somehow when installing it. It was a challenge..and make sure the white plastic ring is seated properly or replace it with a metal clamp of some sort.