Yamaha F60A

Released in mid-2001, the F60A is a bored-out version of the F50A introduced to the Australian market in the mid-'90s. The F60A is a four-cylinder, four-carburettor version of the three-cylinder three-carbie F40B, and increasing the cylinder bore 2mm over the F50A has made a world of difference to the more recent outboard's torque output and power-to-weight ratio.

The F60A has been an absolute success for Yamaha Motor in both the fresh and saltwater markets, despite its being a carburetted motor compared to the Mariner/Mercury EFI F60 - which essentially uses the same powerhead.

According to owner reports, it has been a very reliable motor, with carbie tuning problems only appearing after the motor has clocked up 800 to 900 hours. My freshwater angling readers - who clock up this number of hours at mostly Dead Slow Troll in a couple of years - have told me that slop develops in the complex linkages between the four carbies, resulting in irregular running at low speeds. But resolving this is simply a matter of adjusting the linkages or replacing them, and tuning the carbies using a vacuum gauge tapped into each intake manifold and ensuring there's minimal variation between each manifold.

As with the F40B, the F60A has a cold-start primer system and CDI-microcomputer ignition that ensures instant starting hot or cold without raising the fast idle lever on the remote control box. The ignition timing is advanced during both cold starts and normal operation and is connected to a comprehensive engine protection system. For example, should the engine either overheat, over-rev or suffer oil pressure loss, the revs are automatically reduced to 2000rpm.

Every motor I've tested is so quiet when idling, the only noise is the splash of the pilot water discharge - and noise levels only really become noticeable when the engine revs are above 3500 due the carbie induction roar.

Not having run an F60A for two years, in July I tested two F60As on very different boats, although both motors were running 13in pitch alloy props. One was brand new, while the second privately-owned motor had accumulated about 13 hours. Both started instantly, warmed quickly from cold and never blew any oil smoke. Providing the antiventilation plates were kept at least three-quarters immersed, power astern was very good, with instant throttle response when manoeuvring and no hesitation between the idle and main carbie jets.

The first boat was a Haines Hunter 470 Breeze cuddy cabin, which displaced 850kg including three adults. Trolling unobtrusively at 700rpm, the Yammie averaged 3.1kmh using 0.8lt/hr, while at 1000rpm the average was 5.8kmh - and at 2000 revs it returned 9.7kmh. A clean plane was achieved at 24.1kmh on 3500rpm, although at least three quarters throttle was needed to plane this hull, which has a relatively short planing surface.

Cruising quietly on 4000rpm, the average was 32.2kmh using 7.7lt/hr, and through tight figure-eight turns at these revs there was some prop ventilation - but at Wide Open Throttle we could still converse normally at the helm. The average was an impressive 53.7kmh at 5600rpm using 19.6lt/hr.

As expected with the lower hull weight (680kg including two adults) and shallower-deadrise hull, the Trailcraft 4.5m Runabout required less throttle opening out of the hole and had a slightly higher WOT average speed.

Due to a problem with my handheld GPS we were unable to record speeds below 10kmh, but at 2000rpm the average was 14.1kmh - adequate for trolling offshore - while a clean plane was achieved at 25.2kmh on 3400rpm. At 4000rpm we averaged 36.2kmh, and through tight figure-eight turns at these revs there was no prop ventilation.

The WOT average speed was 54.9kmh on 5700rpm and, due to the solid hull that absorbed any harmonic vibration, we were able to hold a normal conversation at the helm. Servicing the F60A is straightforward, with an initial service at 10 hours then every 50 hours or six months. The waterpump impeller should be replaced every 100 hours or once a year, and the camshaft timing belt should also be checked during this service for any tears.

The F60A has a two-year warranty for recreational applications and complies fully with US EPA 2006 emission regulations.