repowering

[gerlots]

I have a 2007 vintage R25 with the 110 hp YANMAR. Has any repowered with a larger engine, if so what?

 

[nzfisher]

I am curious as to why you are repowering. Do you think your Yanmar is worn out? Or are there other reasons. If you think it is no longer viable how many hours are on it.

 

[Scottfree]

I have the classic R29 and think it's the greatest boat in the world. Well it's the only boat I've ever owned so I'm not much of an expert. I have given much thought to repowering. We spend hours cruising at 6-9 knots and we have the 260 Hp Yanmar. I think I burn more fuel giving it the obligatory run at higher rpm to de grunge it than I do cruising. Now I'm not interested in a numbers debate but here's my thoughts.

Take out the Yanmar and attach it to a mooring ball.

Install an electric engine and batteries and all the other stuff to make an electric boat. Cruise at hull speed. Add diesel generator which I already have! For when I screw up and go cruising! The great loop comes to mind. My cruising speed will be par with sail boats. They seem to flow nice in traffic. Electric is quiet, and I can add lots of batteries before I reach the weight of the Yanmar.

Any thoughts on this? I need 25 HP to reach hull speed but 260 HP to double it. Again I don't want to argue the numbers but that's close enough for discussion. My boat weighs a lot with the wine cellar full. I guess if speed is your thing then maybe just buy a different boat. Or do like me and ride a BMW R1200RT and get all the speed you can handle at a tenth the price!

I encourage someone to repower a Ranger and let us know how it works, costs and all the good information. I'm too cheap to be the first guy to try it?

 

[Levitation]

Roam has put more hours and more miles on their tug than any owners I know of. It is 110 hp. Does not seem to limit them at all and Roam can be found anywhere from the East Coast to Glacier Bay Alaska. Drop Rich an email and get his opinion.

 

[walldog]

I have the classic R29 and think it's the greatest boat in the world. Well it's the only boat I've ever owned so I'm not much of an expert. I have given much thought to repowering. We spend hours cruising at 6-9 knots and we have the 260 Hp Yanmar. I think I burn more fuel giving it the obligatory run at higher rpm to de grunge it than I do cruising. Now I'm not interested in a numbers debate but here's my thoughts.

Take out the Yanmar and attach it to a mooring ball.

Install an electric engine and batteries and all the other stuff to make an electric boat. Cruise at hull speed. Add diesel generator which I already have! For when I screw up and go cruising! The great loop comes to mind. My cruising speed will be par with sail boats. They seem to flow nice in traffic. Electric is quiet, and I can add lots of batteries before I reach the weight of the Yanmar.

Any thoughts on this? I need 25 HP to reach hull speed but 260 HP to double it. Again I don't want to argue the numbers but that's close enough for discussion. My boat weighs a lot with the wine cellar full. I guess if speed is your thing then maybe just buy a different boat. Or do like me and ride a BMW R1200RT and get all the speed you can handle at a tenth the price!

I encourage someone to repower a Ranger and let us know how it works, costs and all the good information. I'm too cheap to be the first guy to try it?

I think you have a great idea. There is at least one company doing very similar to what you describe.

http://www.yachtworld.com/boats/2015/Gr ... ehYNp3BzGc

But I feel you should carry it a bit farther. Dakota Creek Industries here in Anacortes built a ROV Tender for Candies Marine in Louisiana. It had four 5000 hp electric motors operating props on swivels at each corner of the vessel. These motors were powered by diesel generators and GPS computer controlled able to remain at a precise location with a very few feet (inches). Then you could have a box with a joy stick that you carry around with you anywhere on or near the boat to operate it. Downsizing this to an R29 would make a very interesting project. You may have to sell your R1200LT to finance it though.

 

[Favunclerich]

OK Denny, I'll bite. I believe that you are asking for my opinion on the pros and cons of an R-25 Classic equipped with a Yanmar 110 HP 4JH4-HTE versus a larger engine.

The 110 HP has been a great engine for me. We've put over 10,000 NM on Roam with no engine problems. All the engine work that I've done can be classified as routine maintenance. There were a few dozen 2007 and 2008 R-25's built with 110 HP engines. One made multiple trips to Alaska, one completed the Great Loop, others have run the ICW down the East Coast to the Florida Keys and countless other cruises. I'm aware of two that plugged up the fuel filters after buying contaminated diesel, but this is not the fault of the engine. One owner had to replace the turbocharger after many hours of running at almost exclusively slower speeds. We make sure to run Roam at 2900 RPM or higher for at least 15 minutes each day to prevent this. Other than this, I'm not aware of any other problems, recalls or service bulletins. I think that it's fair to categorize the 4JH4-HTE as very reliable.

The maintenance on the 4JH4-HTE is relatively easy and inexpensive. There is no computer and I've watched other boat owners marvel at the accessibility around the engine. I can change the impeller in less than 20 minutes. The oil is not synthetic and sold at Walmart for $13/gallon. I use only about one quart between changes, and this hasn't changed over 1700 hours. The air filter can be cleaned in 10 minutes using a penny's worth of dish soap. The bronze mixing elbow doesn't corrode, and there are no engine zincs to replace. There are a couple of maintenance disadvantages. The valves require adjustment every 1000 hours and there is no belt tensioner, so this has to be done occasionally as well.

The engine is reliable, but an R-25 equipped with 110 HP is slow, particularly if the boat is heavy. Roam tops out at 13-15 knots lightly-loaded in good conditions at wide-open throttle. She'll cruise at 10-11 knots for extended periods if it's not hot and the tanks are not full. When I load her up with full tanks, cruising gear and my 53 pound dinghy, the cruising speed drops to 8.5 to 9 knots. It makes little sense to use four times as much fuel to go 3 knots faster. I know other owners who carry generators, extra batteries, large coolers, outboards and hard-bottom dinghies on the swim step weighing over 100 pounds. These boats are are even slower.

We do most of our cruising at 6.5 knots, 1800 RPM and slightly more than one gallon of diesel per hour. Weight has insignificant effect on speed when Roam is not trying to plane. I'm a former sailor and quite happy at 6.5 knots. Under most conditions it's smoother and quieter than running fast. We only use the extra power to exercise the turbo or if we are doing an exceptionally long day; usually to avoid forecast weather. Sometimes a little faster can help the steering in quartering waves.

But some people cannot be happy cruising at 6.5 knots, so what are the choices?

One R-25 owner in Florida has his propeller pitch changed so that he can run fully laden at full power without overheating. He told me that he gets an extra knot or two, but there is a fuel economy penalty.

I know of one owner who traded in his 110 HP R-25 Classic for a newer 150 HP version. The boat was loaded with all sorts of heavy equipment. He sold the second boat a year or two later, so I don't think the extra horsepower was the answer to his problem.

I also know two owners who traded their 110 HP R-25's for R-27's with 180 HP Yanmars. Both seem quite happy with their upgrades. The R-27 has a lot of nice features and will legitimately cruise at 12 - 15 knots heavily laden. The engine is quieter. But, maintenance is more expensive and difficult. We've buddy-boated for thousands of miles with an R-27. They have to slow to our speeds to travel with us, and they use about 30% more fuel.

A Cutwater 28 is even faster.

Or you could try to replace your engine with a 150 HP Yanmar or Cummins. I don't know the cost, but guess that it would be over $20,000 all-in. The prop would likely change as would much of the plumbing. The bigger engines are computer controlled, so you'll also have to change the instrumentation. A quick check of used boat prices suggests that you are unlikely to recover most of the cost. It might be better to sell your boat and buy a used R-25 with a larger engine.

Another commenter suggests replacing the engine with a motor and a generator. I'm an engineer, and this sounds like a fun science project, but I would never risk it with my boat or money.

Happiness is a decision, not a condition. I've decided to be happy at 6.5 knots, enjoy the scenery and smell the roses. Roam is not for sale. Her 4JH4-HTE will be lovingly maintained to last as long as possible. Good luck with whatever you choose.

Best Regards,
Rich

 

[gerlots]

I have a 2007 vintage R25 with the 110 hp YANMAR. Has any repowered with a larger engine, if so what?

A simple question seemed to bring the hair up on some necks. Curiosity is what moves civilization foreword. I too Have worked As a Marine Engineer all of my adult life. And I still wonder about lots of things.

 

[Irish Mist]

I like the electric idea and use the generator to keep the batteries topped up
🙂

 

[Boatdreamer]

Diesel electric has been done in larger boats already. Nordhavn did a 76 footer back in 2005-2006 and it didn't work out so well. I believe the owners switched back to diesel power. If you Google it, you'll find some articles about it. As far as repowering a R25 that's running well, not sure I'd spend the money for a larger engine to get a few extra knots. That said, I could use that as an excuse buy an R31! Honey, I think the engine is blown (not really) and we need to sell our boat ASAP!

Tim
Gratitude