1987 Johnson/Evinrude CU Outboards 35A thru 55 Service Manual, Page 205Get this manual
Trim Tab AdjustmentAll Models The boat may be slightly easier to steer in one direction or the other due to steering forces or other reasonsTo check this, run the boat in straight line with balanced load in an area where current and wind will not be factor
INote' single trim tabofadjustment will only relieveconditionsNo steering effort under one set speed, trim and loading
single setting can relieve steering effort under all speed, trim and loading conditions1Turn the steering wheel in both directions to determine the direction that requires the least amount of steering effort
Loosen the trim tabIf the boat pulls to port, move the rear of the trim tab to port pulls to starboard, move the rear of the trim tab to starboard
3Reference numbers, thru 6, are embossed on the trim tab for ease of adjustmentAlign the reference number with the recessed screw or the embossed line4Retighten trim tab screw and recheck steering effort in both directionsRepeat procedure until steering effort is equal in both directions5After final adjustment, tighten the trim tab screw to torque of 216-240 inIbs(24-27 Nm)