Re: 1988 115HP Non-start issue
Cranking speed is critical to starting, too slow and the electrical system cannot generate to voltage to operate.
Second, did it start again when you got it back home?
A lean carb idle mixture can start and seem fine on the garden hose but once in the water the water column in the lower leg creates back pressure requiring a richer fuel mixture.
Adjust idle mixture to best idle on the hose PLUS almost 1/4 turn fatter (CCW) readjust once on the water to best idle while IN Forward gear PLUS almost 1/8 turn fatter to provide the additional fuel necessary for acceleration.
Rapidly open the throttle to WOT, any lean cough, bog, or hesitation, further richen the idle just the width of the screwdriver blade slot and retest.
Repeat to perfection, then enjoy the satisfactio of a job well done.