Outboard motor · 20 HPYamaha F20LMHB
formerly F20GMHL
TillerInstallation 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 F20LMHB — 20 HP
Yamaha F20LMHB is a four-stroke outboard motor rated at 20 HP (14,7 kW at the propeller shaft), successor to the F20GMHL. Engine: SOHC, rzędowy 2, displacement 432 cm³, wtrysk paliwa. Dry weight: 56–66 kg.
The tiller version — you steer directly with the handle, with throttle and shift at hand, no console or cables. A practical choice for inflatables, tenders and smaller RIBs. The model has manual pull start and manual angle adjustment (trim in several positions).
Shaft length L (20″ / 508 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: 551 mm.
Fuel consumption at full power according to Yamaha: 7,5 L/h @6000 obr/min. The F20LMHB is within the power range the shipyard recommends for the GRAND S420 N. 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 F20LMHB
| 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 (L shaft) | 1233 mm |
| Transom height (L shaft) | 551 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.
