1990 Johnson Evinrude "ES" Colt/Junior thru 8 Service Manual, P/N 507870, Page 187Get this manual
Midsection Adjustments Tilting Friction
rJl Tighten the tilt shaft nut only enough to hold the motor in any
position of tilt
DO NOT overtighten, as doing so will increase the pressure required to tilt the motor when an obstruction is hitFailure to tilt when hitting an obstruction can cause serious damage to the motorSteering Friction
Igl Adjust