1997 Johnson Evinrude "EU" 9.9 thru 30 2-Cylinder Service Manual, P/N 507263, Page 201Get this manual
COA2674
Twist-Grip Throttle Service20 thru 30
Disassembly
1IUSing OVIC Twist-Grip Throttle Remover, PIN 390767, depress the grip detentsTighten screw and remove the grip by pulling grip and turning the idle adjustment knob clockwise2Remove the helix halves