Repowering a 30-year old Dyna 53 with a John Deere marine engine
by Power Equipment 2 Jun 2020 11:30 UTC
A quieter, more powerful `Five O'clock Somewhere` introduces her confident murmur to the local marina, declaring that she is ready to undertake family journeys out to the Great Barrier Reef and beyond © Power Equipment Pty Ltd
The owner of a North Queensland-based Dyna 53 sought advice recently on the best option for repowering his 30-year-old vessel.
The results in a quieter-running, smoothly powered vessel are soon to have eyes opening wide and heads turning when other skippers realise just how good a John Deere marine engine delivers on the water.
It is what some skippers might call a postcard day on the water off North Queensland as the recreational vessel MV Five O'clock Somewhere, a Dyna 53, is put through her paces with a new pair of John Deere 6090SFM85 engines.
The near 60 feet of flybridge motor yacht (built in the 1990s) is dominating calm waters and a light breeze doing around 25 knots with a relatively quiet baritone tune from the exhausts that only comes from quality American steel - a song that is certainly set to attract plenty of listeners in boating circles.
Owner Michael Day was happy to take the advice of local diesel and marine fitout specialist Brad Belcher from Belcher Diesel Service on the recommendation of John Deere powerplants.
Brad saw the 6090SFM85s as the ideal solution for the repower needs in Michael's recently acquired Dyna 53.
Replacing an aged set of two-stroke diesels rated at the 450hp-mark each, the new John Deere engines were always going to be nautical miles ahead of their predecessors in technology and near smoke-free operation. The M5-rated variant of the 6090SFM85 engines installed also deliver an extra 100hp (550bhp @ 2,500rpm) each but are an environmentally pleasing Tier 3 EPA commercial marine emissions standards engine.
They are a six cylinder, in line, four-stroke overhead valve marine engine and are part of a suite of John Deere marine power that now ranges from 80 horsepower to the 750 horsepower mark.
The John Deere 6090SFM85 (M5 rating) is recreational and light-commercial rated for users who may be looking to put anything from around 300 to 1,000 hours each year of running time on the water.
"Any boat without good engines... is really just a bucket!"
"And any boat without good engines is really just a bucket," says owner Michael Day when asked about his views on the John Deere repower.
While it may be a little harsh to put the comfortable accommodations aboard his Dyna 53 in the "bucket" category, it is the low-revving, high torque delivery of the 6090SFM85 engines that really shines under way.
It is power delivery that comes with a confident note when listening from the outside, but suprisingly quiet inside the vessel with its lower revs and common rail fuel injection. A comfortable conversation is easy now inside the vessel whilst under way - a courtesy not afforded passengers inside with the old engines.
The first thing you notice about the Dyna's new engines is the smoothness of power, zero vibration and a power curve that simply doesn't have any flat spots.
New, precision stainless engine bedding and refit attention to detail has helped with smooth power outcomes.
Belcher Diesel Service put serious thought and precision into the new engine beds, and also engineered custom transmission brackets to cradle the engine and ZF 305-3A gearbox packages supplied by Power Equipment.
The transmissions coupled with the new John Deeres are a 2.250:1 ratio for optimum performance and will be assured long, reliable service with custom transmission oil coolers (again supplied by Belcher Diesel Service) to assist with running in warm tropical North Queensland waters.
Any boat owner looking to refit with quality engines like the John Deeres would be well advised to learn from the detail that went into Five O'clock Somewhere's refit - it is a gold class example of ensuring reliabililty into the future.
Not only did Belcher Diesel Service install electronic controls on the flybridge (and docking controls in the cockpit), they also engineered a stainless exhaust system for the engines to ensure correct breathing and backpressures.
Sea water strainers and primary fuel filters were all renewed, and water tanks were also replaced during installation because of easy access whilst the old engines and generator were removed.
Removing and installing engines was done on-water at a service pontoon in Five O'clock Somewhere's marina, saving thousands in slipping costs and avoiding the cost of delays whilst waiting for parts or expertise.
It is a credit to Brad Belcher and his Belcher Diesel Service team when you consider the planning that went into an on-water installation of the new John Deeres, with crane logistics, multi-deck cutting for access to the engine room and even timing for removal and installation relating to tides in the region (tides can range to nearly four metres in this part of North Queensland).
All well thought-out work that has made sure the gleaming "white bucks" in the engine room are true deliverers on the water.
Four valve cylinder heads, turbocharging with air-to-seawater aftercooling and high capacity heat exchangers are all part of how this 9 litre engine delivers its power curve.
It's the brains of the John Deere engine that takes those mechanicals from pure diesel grunt to a much sweeter, cleaner, quieter and more efficient tune however.
High pressure common rail fuel injection delivers the go-juice to the 6090SFM85 with the highest possible precision and full electronic engine control ensures multiple engine protections and customiseable features for different vessels.
"I'm extremely pleased with the outcome," Michael says of the performance, "and while my son probably uses and drives the boat more than I do at the moment, there is no doubt about the improvement."
Michael and his family enjoy pointing the nose of Five O'clock Somewhere towards the pristine waters of the Great Barrier Reef some weekends, a two-plus hour run off the coast of her home berth in Townsville. He also plans to use the boat on four or five week adventures should retirement allow more time on the water in the future.
They promise to be reliable runs to the Great Barrier Reef too, with the John Deere's attention to maintenance, serviceability and fault diagnosis among the leading features of these marine engines.
For example, the 6090SFM85 boasts water-cooled exhaust manifolds, eliminating external fittings that can leak or break. The engines also have multiple service variations with either side dipstick and oil fill options and remote oil and fuel filter options for easier engine room accessibility if needed.
Couple those features with an ECU that delivers one of the most advanced fault code diagnostics on the market and with proper servicing you should have a virtually bullet-proof engine for years to come.
It is far from sunset days for this near-30 year old hull with Michael's decision of new power just one of the number of upgrades worthy of her luxury heritage and comfortable, twin cockpit levels and spacious aft master cabin.
During unofficial testing with full fuel and water tanks, Five O'clock Somewhere clocked a 27.5litre per hour (per engine) fuel burn for 10 knots @ 1,500rpm. At just over 2000rpm and a 66litre per hour (per engine) fuel consumption she delivered a comfortable 16 knots.
While the John Deeres can consume up to 115litres per hour at full 2,500rpm rated engine speeds, on the day of running they were consuming around 110litres per hour for around 23knots into the breeze and against a small tidal run at 2,500rpm.
Says Brad Belcher of Belcher Diesel Service: "From the first time we took her out through the heads and pushed down the throttles on the new John Deeres, we just looked at each other and couldn't believe the difference these engines offer."
"The power delivery is just so smooth, it's a completely different boat," says Brad.
While John Deere may be a new player in the North and Far North Queensland marine market, if the brand's domination across the agricultural sector is anything to go by the future is looking very bright for John Deere marine engines and Power Equipment.
What's that saying Brad? Nothing runs like a Deere!