Disconnect and ground the spark plug leads to the power head to prevent accidental starting.
Remove the propeller as described in this chapter.
Tilt the outboard to the fully up position and engage the tilt lock.
Shift the gearcase into the forward position. Rotate the propeller shaft while shifting to assist full gear engagement.
Mark the trim tab position with a white grease pencil or china marker. See Figure 11. Remove the retaining screw and trim tab.
Remove the four screws (two on each side) and washers, and one locknut and washer in the trim tab cavity securing the gearcase to the drive shaft housing. See Figure 12.
Pull the gearcase straight down and away from the drive shaft housig.
Place the gearcase in a suitable holding fixture or on a clean workbench.
SYNCHRONIZATION AND LINKAGE ADJUSTMENTS
THROTTLE POSITION SENSOR (TPS) ADJUSTMENT
The correct operation and setting of the TPS is critical to achieving the correct air/ fuel ratio, High TPS voltage provides a richer air/ fuel ratio.
Low TPS voltage provides a leaner air/ fuel ration. Adjustments to the TPS within the specification may be used to fine tune the idle air/ fuel mixture.
Never adjust the TPS out of the specified range. Only use a digital multimeter for the following test. A test harness is required for this procedure.
Use test harness part No. 91-816085 for 1998 and 1999 models.
Use test harness part No. 91-859199 for 2000-on models.
NOTE: Verify the correct idle speed before adjusting the TPS. If the idle speed is changed, readjust the TPS setting. It may be necessary to go back and forth between idle speed and TPS adjustment more than once to get both systems correctly adjusted.