I use the same motor on one of my sneak boats. Well, mine is an '85, but I think it's the same thing. The most frequent and useful adjustment I routinely make is to turn the low-speed knob out a bit to richen the fuel/air mixture for super slow running while setting out longlines. This enables me to run the motor slow enough that I can look down and see the individual blades on the prop as it is turning. I would like to leave it like that all the time, but it adversely affects the smoothness of the motor at any speed above dead slow. I just turn it out while I'm setting up the rig, then turn it back to its normal position for the rest of the day. When tuning up the motor, the last thing I do when adjusting the carburetor is to reinstall the high-speed and low-speed knobs pointing directly toward each other, like the owner's manual says. This makes it easy to return the adjustments to their default positions if you have temporarily tweaked them to compensate for severely cold weather or whatever.
Edit: I just noticed Brandon's post above and it appears there are minor year-to-year differences in these motors. My manual says the default starting point for both high-speed and low-speed needles is 1 1/4 turns from bottomed. Like I said, mine is a 1985 motor. Anyway, the same basic rules apply once you have it set up.
