Review: Honda BFP60 4-stroke Outboard Engine

By: Andrew Norton, Photography by: Supplied

Presented by
  • Trade-A-Boat

Going deep with high-powered gearing.

 

HONDA-BFP60-OUTBOARD-ENGINE-REVIEW.jpg

Max Thrust

The concept of fitting a lower-unit from a powerful engine onto a less powerful one sure ain’t new. A larger lower-unit with deeper gear reduction provides more thrust, pushing work boats and heavier planing hulls without the need for a more powerful power-head.

Outboard Marine Corporation was the first to do this with its three-cylinder Triumph 55 way back in 1968. As with its twin cylinder 50 counterpart, released in 1971, both engines had a massive 2.42:1 gear ratio that enabled power-head torque to be efficiently converted to thrust at the prop and swing coarse-pitch props.

Other manufacturers followed suit with high thrust or deep gear ratio versions of existing engines. This gave boaters the choice of tall ratios for lightweight hulls or deep ratios for heavier hulls.

The trade-off with bigger lower-units and deep ratios is the drag at planing speeds which prevents these engines from being used on performance hulls. But for family boats where wide open throttle (WOT) is rarely used, the ability of a hull to maintain a clean plane in rough water is more important. A deep ratio and the correspondingly larger prop enables the engine to hold a planing attitude at lower rpm. And in some cases the engine can actually compete overall with a more powerful engine having a taller ratio, saving initial set up costs and reducing weight on the transom.

Honda’s BFP60 is one such engine. The standard ratio is 2.08:1, fine for lighter hulls and tiller steering where a deeper ratio would create excessive prop steer torque and make driving the boat a real work out (like Yamaha’s Enduro 60). But the BFP60 version has the lower unit and gear ratio of the BF75, which is 27 per cent heavier. Sure this engine will always outperform the BFP60 but less weight on the transom narrows the gap because the BFP60 can maintain a clean plane at lower speeds, saving fuel and providing better fore and aft hull trim. The BFP60’s 2.33:1 ratio is obviously nowhere near as deep as the

Evinrude E-TEC 60’s 2.67:1 ratio but like all marine engines is a compromise between load-pushing ability and reasonable planing performance. Frankly, for non-commercial applications on planing hulls the E-TEC 60 ratio is a touch too deep, whereas the BFP60 ratio is just about right.

THE MECHANICS

The BFP60 is in a tough market with both three- and four-cylinder competition all trying to gain a share of this popular engine size. Having three cylinders makes the Honda lighter than its four-cylinder Mercury and Yamaha competition, with a side benefit of slightly higher vibration levels that can gently massage body flab when trolling. Though unfortunately for fatties like me, not as high as the twin cylinder E-TEC 60.

A three-cylinder engine is always cheaper to manufacture than a four-cylinder unit, which is why Suzuki’s DF60 also has three cylinders and servicing is not quite as complex (three versus four fuel injectors etc). Originally the DF60 had a four-cylinder engine straight from the Suzuki Sierra 4WD but was fairly hefty for its output, so it’s understandable Suzuki opted for a much smaller displacement three-cylinder power head. Despite having three cylinders, the BFP60 has the largest piston displacement of any 60 on the Australian market.

Like its more powerful counterparts, the BFP60 has BLAST and ECOmo. These make a significant difference to hole shot performance and midrange fuel efficiency. BLAST functions by enriching the air/fuel ratio from the normal 14.7:1 to 12:1 when the throttle lever is advanced rapidly, while ECOmo leans out air/fuel to 18:1 once the hull is planing and up to about 5,000rpm. At WOT the air/fuel ratio is back to 14.7:1.

Because Honda realises that boaters can never have too much power for on-board electronics, the BFP60 has a 27-amp under flywheel voltage-regulated alternator that provides up to 22-amps of dedicated battery charging capacity. An external starter battery of at least 60 amp/hour is needed as the engine has conventional multipoint EFI. It’s a shame Honda didn’t opt for a self-contained EFI as in the E-TEC 60.

Having12 valves operated by a single overhead camshaft, the engine is likely to be of an interference design so checking the camshaft drive belt annually for fraying and replacing it every 800 to 1000 running hours is essential. At least adjusting valve clearance is easy using just a feeler gauge and 10mm spanner. Honda really shows its engineering prowess here!

Power head access is good with the engine oil dipstick and fuel and oil filters easily reached. For temperate climates the recommended oil is Honda’s own SAE 10W30 though if not available Quicksilver FCW (four cycle water cooled) SAE 10W30 would do the job just fine.

Recommended oil and filter change intervals are every 100 running hours or annually after the first 20 hours.

The recreational usage warranty is an incredible seven years, still the best in the outboard industry.

ON THE WATER

Mounted on a 4.9 metre Stessl aluminium runabout and swinging a fat bladed 14-inch pitch stainless steel Solas prop, the demo BFP60 returned much better performance than expected – even when pushing four adults. It started instantly hot or cold with no oil smoke appearing, nor (unlike the E-TEC 60) was there an oil smell when backing upwind.

Providing the anti-ventilation plate was kept immersed power astern was good, useful for backing out of shallow water. Trolling at 800rpm there was just a slight tremor through the hull with less overall vibration than the E-TEC 60.

With the engine warmed up the BLAST system was really effective in quickly getting us out of the hole, though due to lower unit drag reaching WOT was not so rapid. However through tight figure of eight turns at 4,000rpm the Solas had tons of bite with no prop ventilation. Enough to throw one unsuspecting occupant clear across the stern!

At or near WOT the engine was quiet with less exhaust resonance than the E-TEC 60. The combination of BLAST and ECOmo made this engine fun to drive while still returning excellent midrange fuel efficiency.

THE WRAP

Honda offers boaters a great package in its BFP60. For its output the engine has plenty of grunt while remaining frugal to run. And being a Honda, with regular maintenance it should
return years of enjoyment on tinnies to 5.2 metres or older fibreglass hulls like the Haines Hunter 445R.

PERFORMANCE AND FUEL CONSUMPTION

Single BFP60 on 4.9 Stessl runabout swinging a 14 inch Solas prop. Average of two way runs on Port Stephens NSW, calm water. Total displacement 910kg
including three adults. Range is in nautical miles from a 25 litre portable fuel tank with a 10% reserve.

Rpm Kts L/h Total Range
800 (trolling)  2.4  .06  90
1000 3.0  1.0  68 
2000 5.1  2.6  44 
3000 (planing) 9.4  5.7  37 
4000 (cruise) 16.7  7.4  51 
5000 (max cruise) 24.0  13.5  40 
6000 (WOT) 28.0  20.6  31 

Time to plane was 3 seconds and 14 to reach WOT.

 Test conditions as above but with 4 adults aboard and total displacement 990kg.

Rpm Kts L/h Total Range
800  2.4  0.6 90
1000 2.7  0.9  68 
2000 5.4  2.7  45 
3500 (planing) 11.9  7.5  36 
4000 (cruise) 16.7  7.8  48 
5000 (max cruise) 23.2  14.1  37 
5700 (WOT) 26.7  19.9  30 

Time to plane was 4 seconds and 15 to reach WOT.

Note how the additional load barely affected performance or fuel efficiency.
From trolling to fast idle there was no difference.

This review was originally published in issue #510 of Trade-a-Boat magazine. Subscribe today for all the latest boat news, reviews and travel inspiration.

 


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