Small Outboard Jet Motor: When It Makes Sense and When a Prop Wins
A jet lower unit lets a boat skim over gravel that would chew a propeller. It also costs you a big slice of push. Here is how to decide, and how to run shallow water with the motors we actually sell.
A small outboard jet motor is a regular propeller outboard fitted with a jet pump lower unit instead of a propeller, so nothing hangs below the hull and the boat can run in very shallow rivers. The trade-off is that it loses roughly a third of its thrust.
Tane, the shingle bar and two bent props
Tane fished a river mouth where the channel moved after every flood. Some mornings there was a metre (3 ft) of water over the bar. Some mornings there was a hand’s width. His 15 HP had already donated two propellers to the shingle, and his mate kept telling him to “just go jet”.
So Tane priced it up. A jet conversion would keep the lower unit out of the rocks, but the motor would push like something much smaller. To get the same performance he would need a bigger, heavier powerhead, and his 3.8 metre (12.5 ft) boat’s plate did not allow it.
Instead he changed how he ran the bar. He set his tilt to its shallow-water position, crept across at idle with one person moved forward, and kept a spare prop and a pin kit under the seat. On the calmest days he switched to a small Torqeedo, which he could tilt up in a second and push through the shallows without fuss.
A season later: zero new props, every fishing spot still reachable. Sometimes the best jet is good technique and the right shaft.
Is a small outboard jet motor better than a propeller?
Only for very shallow, rocky rivers. Everywhere else a propeller outboard pushes harder, burns less fuel and costs less.
| Factor | Jet lower unit | Propeller outboard |
|---|---|---|
| Draft | Very shallow, nothing below the hull | Needs water for the gearcase and prop |
| Thrust | Roughly a third less for the same powerhead | Full rated thrust |
| Fuel use | Higher for the same speed | Lower |
| Low-speed control | Weaker, harder to steer at idle | Good steering and reverse |
| Weed and debris | Intake grate can clog | Prop can foul, easier to clear |
| Best fit | Shallow rocky rivers | Harbours, lakes, inlets, estuaries |
How do you run shallow water with a propeller outboard?
Use the right shaft length, the motor’s shallow-water tilt setting, and slow, deliberate speed. Those three habits solve most skinny-water problems without a jet.
- Get the shaft right. A short shaft on a 38 cm (15 in) transom keeps the gearcase as high as it can safely sit.
- Use shallow-water drive. Many small outboards have a tilt position that lifts the leg partway while still running at low speed.
- Slow down early. Drop to idle before the shallows, not when you hear the first scrape.
- Shift weight forward. Moving a passenger toward the bow lifts the stern and the prop.
- Read the water. Ripples, colour changes and bird legs tell you where the channel runs.
- Carry spares. A spare prop, shear pin or split pin and the right spanner turn a bad day into a five-minute fix.
Shallow-water friendly motors we sell
Light, short shaft and quick to tilt. Prices are starting prices in USD.
We do not sell jet outboards or jet conversions. Browse all short shaft motors for the lowest-riding petrol options.
Small outboard jet motor: FAQ
How much power does a jet outboard lose?
As a rule of thumb, roughly a third of the thrust compared with the same motor running a propeller. That is why jet owners usually choose a larger powerhead.
Can I convert my small outboard to a jet?
Aftermarket jet lower units exist for some models, but fitment varies by make and year. Talk to a qualified marine technician before buying one, and check your capacity plate.
Is an electric motor good for shallow water?
Yes. Torqeedo motors are light, tilt up easily and the Travel models can kick up if they strike the bottom, which suits shallow creeks and lake edges.
What does shallow-water drive do on an outboard?
It locks the motor in a partly tilted position so you can motor slowly through shallow water with the prop higher. Run at low speed only and watch the tell-tale for cooling water.
Keep your props and your fishing spots.
Tell us where you launch and how shallow it gets. We will suggest the motor and setup.