Safety first
- • Disconnect power at the panel before wiring.
- • Verify de-energized with a meter.
- • Follow local code — licensed electrician where required.
- • Always check the manufacturer's manual for your exact model.
Boat lift motor — what it is, how it's wired, and how to pick one
A boat lift motor is a reversible single-phase electric motor (almost always 1 HP or 1.5 HP) bolted to the gear-reducer on the lift's drive beam. It spins one direction to wind cable in (lift goes up) and the other direction to let cable out (lift goes down). Below is a non-technical overview, plus links to the full wiring diagrams.
The brands you'll see on a Deco lift
Deco doesn't manufacture motors — they buy them. Per the 2025 Deco Owners Manual, the supported brands are:
- AO Smith — the most common factory motor on new Deco builds.
- Marathon — also very common; wired slightly differently from AO Smith.
- Leeson — heavier-duty option, often on commercial lifts.
- Electra Gear / Elite — wires the same as AO Smith.
- Stainless steel housing — premium upgrade, same wiring as AO Smith.
Note: Aquamatic is not a Deco motor. If you see one, you're on a different brand lift.
How a boat lift motor is wired
Every reversible lift motor has the same six leads (color-coded). They land on three places:
- L1 and L2 — incoming power from the breaker (220V hot/hot, or 115V hot/neutral).
- Two reversing leads — these are swapped to change the direction of spin.
- One common lead and ground — common ties to one side of the line, ground to the case.
On a new Deco build the motor wires don't land on a bare terminal block — they land inside a TEC II receiver (or a drum switch, on older lifts). The TEC box has a printed diagram on the inside of the lid showing exactly which motor wire goes where for your brand. Always use that diagram, not the motor nameplate.
115V vs 220V — which one should you wire?
Deco's standard is 220V single-phase on every lift, and 220V is required on every 4-motor lift. 115V is allowed on small 1-motor lifts but isn't recommended — at 115V the motor pulls roughly double the amps, which means heavier wire, more voltage drop on a long run from the panel, and a motor that runs hotter and lasts shorter.
Most lift motors are dual-voltage. There's a small jumper plate inside the motor's wiring cap; you move it to set 115V or 220V before you ever wire to the controller.
Check voltage drop for your wire run →Lift going the wrong way? Reverse it.
Out of the factory the motor has no preset up-or-down direction — it just spins whichever way the wires happen to land. If you hit UP and the cable spools off instead of winding in, you reverse direction by swapping two specific motor wires. The pair to swap depends on the motor brand:
- AO Smith / Electra Gear / Elite: swap motor
BK ↔ RD - Marathon / GE: swap motor
BK (T5) ↔ RD (T8) - Leeson: swap motor
T5 ↔ T8
Never swap L1 and L2 on any brand — that doesn't reverse the motor, it just shifts where the neutral sits and can damage the controller.
Picking a replacement motor
- Horsepower: match what came off — usually 1 HP for 4500–7000 lb lifts, 1.5 HP for bigger.
- Reversible single-phase — non-reversible "pool pump" motors won't work.
- Dual-voltage 115/230V — gives you the flexibility to wire either way.
- 56-frame — the standard mounting size for a boat lift gear-reducer.
- Marine-duty or TEFC (totally enclosed) — open-frame motors will rust quickly in salt air.
Common motor problems
- Hums but won't turn: usually a bad start capacitor or a stuck centrifugal switch.
- Trips the breaker on startup: wrong voltage jumper inside the motor, or undersized wire run.
- Runs hot / shuts off mid-lift: 115V on a load that should be 220V, or thermal overload.
- Goes the wrong way: reverse the brand-specific pair above — never L1/L2.