Outboard motor · 20 HPYamaha F20SEB
formerly F20GES
Mechanical control leverSteering: mechanical or hydraulic, fitted in the boatInstallation and rigging at the GRAND BOATS Poland service centre in Łężyce. Sold in cooperation with an authorised Yamaha dealer; manufacturer warranty 3 + 2 years at an authorised Yamaha service.
Yamaha F20SEB — 20 HP
Yamaha F20SEB is a four-stroke outboard motor rated at 20 HP (14,7 kW at the propeller shaft), successor to the F20GES. Engine: SOHC, rzędowy 2, displacement 432 cm³, wtrysk paliwa. Dry weight: 56–66 kg.
A motor for remote control from the console — throttle and shift by cables from the control lever (mechanical controls), with mechanical or hydraulic steering in the boat. A proven choice for console boats that is simple to service. The model has electric start and manual angle adjustment (trim in several positions).
Shaft length S (15″ / 381 mm). The shaft is matched to the boat’s transom height so that the anti-cavitation plate runs just below the water surface. Transom height for this shaft according to Yamaha: 424 mm.
Fuel consumption at full power according to Yamaha: 7,5 L/h @6000 obr/min. The F20SEB is within the power range the shipyard recommends for the GRAND G340, GRAND S420 N, GRAND S370 NL, GRAND S370 NS, GRAND S370 N, GRAND S330 L, GRAND S330 S, GRAND S330. At the GRAND BOATS Poland service centre in Łężyce near Gdynia we install the engine, do the rigging and choose the propeller. The engine is supplied in cooperation with an authorised Yamaha dealer; the manufacturer warranty (3 + 2 years) is carried out by an authorised Yamaha service.
Yamaha F20SEB
| Maximum output (at propeller shaft) | 20 KM (14,7 kW) |
|---|---|
| Full-throttle range | 5000–6000 rpm |
| Idle speed | 850–950 rpm |
| Fuel consumption (reference data) | 7.5 L/h @6000 rpm |
| Engine type | 4-stroke, SOHC, in-line 2 |
| Displacement | 432 cm³ |
| Bore × stroke | 65,0 × 65,1 mm |
| Compression ratio | 9,1:1 |
| Fuel system | Fuel injection |
| Lubrication | Wet sump |
| Engine oil capacity | 1.1 L / 1.0 L (with / without filter change) |
| Ignition | TCI |
| Spark plug | DPR6EB-9 |
| Alternator | 16 A |
| Trim | 4 positions |
| Gear ratio | 2,08 (27/13) |
| Gear shift | F-N-R |
| Shaft lengths in the family | S, L (WHP: L) |
| Overall height (S shaft) | 1106 mm |
| Transom height (S shaft) | 424 mm |
| Beam | 378 mm |
| Weight (dry) | 56–66 kg |
| Steering angle | 45° each way |
Source: Yamaha Product Information Guide 2026 (F20G family). Fuel consumption — manufacturer’s reference data.
Boats rated for 20 HP
S420 N
S370 NL
S370 NS
S370 N
S330 L
S330 S
S330
S300 L
