# What is the HIGH and LOW adjustment for a McCulloch Walbro carburetor ?



## Duane Adrian (Oct 13, 2017)

*October 13, 2017*

*I have a McCulloch PRO MAC 10 10s and McCulloch PRO MAC 610.*

*The chainsaw start up and run for a 30 seconds to 1 minute. Then stop. The do not continue to idle. When I press the THROTTLE. The chainsaws remain running. But after awhile the chainsaw just stop running.*

*I have two types of WALBRO carburetor kits. Replaced all gaskets, idle needle and metal screen. *

*Both needed NEW WALBRO carburetor kits. But I need to know what are the screw adjustments for the HIGH and LOWS idle screws. I had to take both screws out to clean the carburetors. I need to know many screws counter clock wise to have the correct idle setting.*

*Any advice or suggestions are appreciated.*

*Duane*


----------



## ray benson (Oct 13, 2017)

Got this out of clymer service manuals for the 2 saws.
Initial adjustment of mixture needles
on Tillotson, Walbro and Zama carburetors
is one turn open for both low and
high speed mixture needles. Make final
adjustment on Tillotson, Walbro and
Zama carburetors with engine warm
and running. Adjust idle speed screw so
engine idles just below clutch engagement
speed. Adjust low speed mixture
screw so engine will accelerate cleanly
without hesitation. Adjust high speed
mixture screw to obtain optimum performance
under cutting load.
Check your inbox for the manuals.


----------

