Black Max BM5020 Operator's Manual page 28

bar, making sure the drive links are seated inside
the bar groove.
 Retighten the bar mounting nuts securely.
 Release the tip of the guide bar and verify the chain
is now correctly tensioned using the guidelines
above.
NOTE: If the chain is too tight and will not rotate,
loosen the bar nuts slightly, then turn the chain
tensioning screw 1/4 turn counterclockwise. Lift
up the tip of the guide bar, retighten the bar nuts
securely, then verify the chain will now rotate
without binding.
NOTE: New chains tend to stretch; check the chain
tension frequently and adjust as needed.
NOTICE:
A chain tensioned while warm may be too tight
upon cooling. Check the "cold tension" before
next use.
CHAIN MAINTENANCE
See Figures 45 - 46.
CAUTION:
Stop the engine and disconnect the spark plug
wire before you work on the saw to avoid acciden-
tal starting and possible serious personal injury.
Use only a low-kickback chain on this saw. This
fast- cutting chain provides kickback reduction when
properly maintained.
For smooth and fast cutting, maintain the chain
properly. The chain requires sharpening when the
wood chips are small and powdery, the chain must
be forced through the wood during cutting, or the
chain cuts to one side. During maintenance of the
chain, consider the following:
 Improper filing angle of the side plate can increase
the risk of severe kickback.
 Raker (depth gauge) clearance.
• Too low increases the potential for kickback.
• Not low enough decreases cutting ability.
 If the cutter teeth hit hard objects such as nails
and stones, or are abraded by mud or sand on the
wood, have an authorized service center sharpen
the chain.
MAINTENANCE
RAKER (DEPTH GAUGE) CLEARANCE
Page 28 — English
FLATS ON TIE STRAPS
≈
.050 in.
≈ .050 in.
Fig. 42
Fig. 43
Fig. 44
.025 in.
Fig. 45
INSPECT
DRIVE
SPROCKET
Fig. 46