How to adjust carb on craftsman 42 cc chainsaw

SOURCE: 42 cc engine

I didn't see a complete engine assembly at Poulan. Ask them.
Handheld (Chainsaws, Trimmers, Blowers, Edgers)
1 (800) 554-6723 or
http://www.poulanpro.com/node4033.aspx

A new cylinder and piston are about $75.00, plus shipping, if available here:
http://www.ordertree.com/modelinfo/POULAN-WEED-EATER/75.59.html
An inquiry for repair at a local saw shop might be worth an inquiry.

An entire new saw PP4218 is $150.00 @ Walmart.
Did you borrow someone else's saw and run it on straight gas? HTH
Lou

SOURCE: HOW DO U AJUST CARB ON A POULAN CHAINSAW 36.CC

Start with "H & L" at 1,5 CCW from lightly seated then tune for performance like this:
Carburetor Adjustment by Madsens.com
http://www.madsens1.com/saw%20carb%20tune.htm
CW is leaner; to lean will destroy the saw. If over tightened closed (CW) the adjustment screw faces are easily marred; marred adjustments are difficult to impossible to set properly.
Clean the air filter; adjusting with a dirty filter can cause a run lean condition once cleaned and the saw run.
There are 2 wav (sound - idle & full – may not be highlighted) files that I find most helpful, I think you will too. I hope this is helpful
Lou

SOURCE: Chain will not stop spinning

I would say it has an air leak, through a gasket or crank seal, make sure the carb is tight and sealing properly.

SOURCE: i have a craftman chainsaw with a 42 cc engine has

90lbs is not enough compression, so yes rebuild, or more fiscal idea is get a new one, unless you can do the labor yourself.