2004 SR Johnson 2-stroke 40, 50HP Service Manual, Page 57Get this manual
INSTALLATION AND PREDELIVERY TRIM TAB ADJUSTMENT
TRIM TAB ADJUSTMENT
WARNING
Improper trim tab adjustment can cause difficult steering and loss of controlA propeller will generate steering torque when the propeller shaft is not running parallel to the water's surfaceThe trim tab is adjustable to compensate for this steering torque
If the boat pulls to the left or right when its load is evenly distributed, adjust the trim tab as follows: With the remote control in NEUTRAL and the engine OFF, loosen the trim tab screwIf the boat pulled to the right, move rear of the trim tab slightly to the rightIf the boat pulled to the left, move rear of the trim tab slightly to the left Tighten the trim tab screw to torque of 18 to 20 ftIbs(24 to 27 Nm)