Review: Yamaha F300 Marine Outboard

Yamaha’s new-generation V6 four-stroke outboards range from 225hp to 300hp and are loaded with power and performance. That’s no surprise given the 4.2L displacement, but the Yamaha Variable Camshaft Timing radically increases throttle response, delivering exceptional power throughout the rev range.

Meanwhile, the Freedom 307’s recommended 600hp rating makes twin Yamaha 300hp V6s an ideal match for the boat’s size and weight.

The big 4.2L capacity has been achieved by a highly advanced thermally applied plasma-fusion process on the cylinder walls. It’s a feature commonly found on high-performance sports cars and means there are also no conventional steel cylinders, yet the walls are 60 per cent harder, allowing more power and torque, better cooling properties, and significantly reduced weight (253kg on a 25in leg; 259kg – 30in).

The V6 is compatible with Yamaha’s new electronic rigging system and its 5in high-contrast LCD multi-engine display, electronic controls, new key switches and start/stop panels, making the package more convenient and flexible, with more information than ever before.

We found the Yamahas smooth to drive on the Grady White Freedom 307. They were nice and quiet on the transom at cruise speeds, and produced good economy for the boat’s size and weight.

YAMAHA F300 SPECIFICATIONS

Make/model Yamaha F300 x2
Type DOHC, 24-valve
60° V6
Weight 253kg (each)
Displacement 4169cc (each)
Gear ratio 1.75: 1
Propeller 15.5x17in

SEA TRIALS

Grady White Freedom 307 with twin Yamaha F300 four-stroke outboards.

RPM	Speed (Kts)	Economy (L/H, combined)
600	5	4.8
1000	6	9.5
1500	8	13
2000	10	24
2500	13	30
3000	18	51
3500	22.4	66
4000	29	90
5000	38	163
5800	43	203

We saw a speed variation around 3-4kt against a full tide and wind at 15kt SE, but delivering similar economy.