Product Manual
31
OREGON® Cordless Tool System 
CHAIN SAW MODEL CS300
MAINTENANCE AND CLEANING 
AA 1214 - F/N 573259
MAINTAINING THE GUIDE BAR
 WARNING: THE EDGES OF A 
WORN GUIDE BAR, PARTICULARLY 
THE EDGES OF THE GROOVE WHERE 
THE CHAIN TOUCHES THE BAR, 
CAN BE EXTREMELY SHARP. USE 
APPROPRIATE HAND PROTECTION.
 CAUTION: THE GUIDE BAR CAN BE 
HOT AFTER CUTTING. WEAR GLOVES TO 
AVOID BURNS.
To even bar wear and maximize bar life, 
flip the bar occasionally.
Wear gloves.
• Remove the battery.
• Loosen the side cover release knob 
slightly, but do not remove the side 
cover.
• Loosen the chain tensioning ring (turn it 
counterclockwise) as far as it will go.
• Loosen the side cover release knob and 
remove the side cover.
• Remove the bar and chain and inspect 
for damage and wear.
• Remove the screw from the back side of 
the chain tensioning gear and remove 
the chain tensioning gear from the 
guide bar (Fig. ).
• Flip the bar (Fig. ).
• Replace the guide bar and saw chain. 
See “Assembling the Guide Bar and Saw 
Chain” section in this manual.
• Tension the chain as described in 
“Tensioning the Saw Chain” in the 
“Unpacking and Assembly” section of 
 this manual.
REPLACING A WORN GUIDE BAR
 WARNING: THE EDGES OF A 
WORN GUIDE BAR, PARTICULARLY 
THE EDGES OF THE GROOVE WHERE 
THE CHAIN TOUCHES THE BAR, 
CAN BE EXTREMELY SHARP. USE 
APPROPRIATE HAND PROTECTION.
When the guide bar becomes cracked 
or has excessive wear around the edges, 
particularly in the groove where the 
saw chain touches the bar, it must be 
replaced. Also, if the nose sprocket is 
worn, has teeth missing or does not turn 
smoothly, the bar must be replaced.
Wear gloves.
• Remove the battery.
• Loosen the side cover release knob 
slightly, but do not remove the side 
cover.
• Loosen the chain tensioning ring (turn it 
counterclockwise) as far as it will go.
• Loosen the side cover release knob and 
remove the side cover.
• Remove the bar and chain.
• Remove the screw from the back side of 
the chain tensioning gear and remove 
the chain tensioning gear from the 
guide bar as described in “Maintaining 
the Guide Bar”.
• Place the chain tensioning gear on the 
new guide bar and replace the screw.
• Replace the guide bar and saw chain. 
See “Assembling the Guide Bar and Saw 
Chain” section in this manual.
• Tension the chain as described in 
“Tensioning the Saw Chain” in the 
“Unpacking and Assembly” section of 
this manual.
FIG. 43 
FIG. 44 










