Ryobi OPP1850 Original Instructions Manual page 19

MAINTENANCE
NOTE: Hold the tip of the bar up and tighten
the bar bolt securely. The chain tension is
correct when the gap is about 3-4 mm.
NOTE: If the chain is too tight, it will not rotate.
Loosen the bar bolt slightly and turn chain
tensioning screw 1/4 turn counterclockwise.
Lift the tip of the bar up and retighten bar bolt
8. Fully tighten the bar bolt and drive case cover.
Bar bolt should have at least 4 turns after finger
3-4mm
tight.
8
2
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