2 stroke experts??

[BLES]

Two Stihl BG86C blowers. One runs reasonably well, the other runs decent at full throttle but doesn't idle well. The one that stalls at idle runs with the primer bulb almost empty. The one that works well runs with the primer bulb basically full.

Does this indicate anything obvious right off? I noticed this on first inspection, but don't know exactly what it means. Wondering if any of the experts here know what this is before I start.??
Thanks.
BLES

[bgsengine]

primer bulb function is only to draw air out of the carburetor leaving just fuel in carb. If it continues to draw air after purging, then you have an air leak into the fuel system somewhere. - Pinholes in fuel lines, leaking diaphragms or carburetor check valves, etc. Any of which would give you running problems. Primer bulb does not need to fill up with fuel at all - all it does is draw fuel through the carburetor, doesnt matter if it is full or empty as long as it draws all the air out of carburetor, but if it keeps drawing air through after extensive purging then you got an air leak as noted.

[KE4AVB]

Either you have a stiffen metering diaphragm or the metering needle lever is set too low on the one that doesn't idle well.

[BLES]

Thanks guys. Will clean carb, install a kit, and check things over.
BLES