Mercury 50 4-Stroke Manual page 56

NOTE: To maintain proper adjustment, the locknut located on top
of the steering friction lever pivot shaft can be tightened.
a - Tighten friction
b - Loosen friction
REMOTE STEERING MODELS
Insufficient friction adjustment can cause serious injury or death
due to loss of boat control. When setting the friction adjustment,
maintain sufficient steering friction to prevent the outboard from
steering into a full turn if the tiller handle or steering wheel is
released.
FEATURES & CONTROLS
a
c
WARNING
!
b
26811
c - Locknut
48