Honda Outboard Motor BF20 Owner's Manual page 34

Shear Pin Change
A shear pin is used to protect the propeller and drive mechanism from
damage when the propeller strikes an obstruction.
1. Remove the cotter pin and the propeller.
2. Remove the broken shear pin and replace it with a new one.
3. Install the propeller.
4 Install a new cotter pin, and spread the ends as shown in the illustration.
COTTER PIN
SHEAR PIN
-SPEAR SHEAR PINS
AND COTTER PINS
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