Congratulations on the new Tug. I no longer deliver outboards but when I did, my suggestion to new owners about buying a spare prop was to wait. The delivered prop is usually set up by the factory based on average load. Depending on the usage of the boat and load the delivered prop is not always the right one. In many cases the delivered prop becomes the spare and the spare can become the proper prop. I told new owners load the boat the way you are going to use it, passengers, gear, fuel, water, then sea trial the prop. The manufacture gives a maximum RPM range for the engine to be propped to. Example: Suzuki 300 HP Max rpm range 5700 to 6300 rpm. When sea trialing the prop @ WOT on smooth water, with what you would consider your max load on board, the way you plan on cruising gear, passengers, fuel, water,....... you would want the engine to be turning close to the maximum rpm I usually shoot for 200 rpm under max. 6100 would be the lowest I would want it to turn. This insures that at no time the engine is loaded down, "Lugging". When you are in big seas and have a prop close to the bottom end of the max RPM range the motor is working hard, "lugging" climbing a big hill all the time. Remember prop load is the same at 1000rpm as it is at 4000rpm or 6000rpm. Boat engines don't have gears, Just Forward and reverse. Proper propping is important.
