jets are very popular in Alaska due to the many shallow running rivers
and streams in the state. AMDS has complete jet kits for your
outboard motor plus parts such as replacement impellers, lines, and
Combining the correct
outboard power and boat design is the “secret” of successfully using
an outboard jet to run in shallow water. Keep it light as possible
since, unlike a propeller drive, you can’t change to a lower pitch
jet drive impeller to increase load capability.
Aluminum is usually the material of choice. It is light, tough and
easy to form in the proper configuration. For outboard jets, the
bottom thickness can range from 1/16” (.063) for 20-50 HP to 3/16”
(.187) for motors up to 225 HP. The lighter gauge is more easily
damaged whereas the heaviest gauge can be a weight problem on
midrange power from 50-100 HP.
The size and shape of the bottom is very important. The object is to
ride on top of the water, which requires a good planing surface, and
to float as shallow as possible when shut down. Bottom should be at
least 48 inches wide and boat length at least 14 feet long.
There is about a 30% power loss when converting to our jet drive. A
suitable outboard jet boat carrying an average load will provide
about 80% of propeller speeds. It’s important to decide what load
you want to carry how many people, gear, fuel, etc. and add the
weight of the boat, motor and battery.
The advantages of Outboard Jet boat include maximum space inside the
boat while still having the ability to operate in less than 6” of
water, relative ease of cleaning out a clogged pump and adjustment
for wear on the impeller and intake liner. AMDS can help you select
select a suitable boat with sufficient HP to handle your total
weight, so you can enjoy fishing and hunting in areas you couldn’t