Past subject: repower older trawlers

[Insequent]

It is not a typo. It is really a big job.

The thing is, because you have great access with the old engines out you do a bunch of other stuff that will need doing before all that long anyway. Project scope grows a lot, more than the items Bill listed I'm sure. And it all adds up.

Re-powering and concomitant refit is only something you do on a boat that you will be keeping for 15 years or so. I'm halfway there - I re-powered in 2012!

 

[ben2go]

You can find those engines here in the us. They put them in a lot of things. I know of 2 with about 300hrs on them. They were power for hospital generators. Maintenance runs, and a couple emergency uses on each. I would put them in any displacement hull under 60,000

I haven't come across one yet. I hope I do when it's time to install the engine in the boat I'm building. The 4b Cummins is perfect for the engine room size and layout.

 

[Bill Blatchford]

The thing is, because you have great access with the old engines out you do a bunch of other stuff that will need doing before all that long anyway. Project scope grows a lot, more than the items Bill listed I'm sure. And it all adds up.

Re-powering and concomitant refit is only something you do on a boat that you will be keeping for 15 years or so. I'm halfway there - I re-powered in 2012!

I hope you are right about the 15 years. My wife and I are 76 years old and plan ob boating for at least 15 more years. We do spend 2-3 months each year on our GB each summer and have for the past 25 years. We will be cruising to Alaska and back next summer. It all comes down to QTR. The boat is stored on the hard in a building 9 months out of the year. Part of our decision was based on the fact that we have replaced and redone pretty much every thing on this boat. I know it well and we did not need or want any thing larger.

 

[Insequent]

I hope you are right about the 15 years. My wife and I are 76 years old and plan ob boating for at least 15 more years. We do spend 2-3 months each year on our GB each summer and have for the past 25 years. We will be cruising to Alaska and back next summer. It all comes down to QTR. The boat is stored on the hard in a building 9 months out of the year. Part of our decision was based on the fact that we have replaced and redone pretty much every thing on this boat. I know it well and we did not need or want any thing larger.

A 42 Classic is pretty much perfect for a couple with occasional guests, so is worth what you have put into it IMO.

 

[Boatingbill]

I haven't come across one yet. I hope I do when it's time to install the engine in the boat I'm building. The 4b Cummins is perfect for the engine room size and layout.

When you are ready let me know. My brother in law has a shop. They do cummins, Perkins, and a couple others. They do a lot of warranty work. He could find you just about anything in short order. They have been around forever, so he hooked me up with a ton of spares for my old 903’s. I have a whole set of injectors as well as a complete fuel pump. I’m buying a complete engine in a week or so. Starting to get hard to find a couple things on these old engines. I found an old boat that had my engines, but the exhaust was very different from mine. Also almost impossible to get the engine out of that boat. The one I’m getting came out of a tractor.

 

[koliver]

One concern about re-using the Velvet Drives with twins: Unless they're CR2s, the outputs will rotate the same as the inputs, so counter rotating engines are required to get counter rotating props. That issue alone would have my Velvet Drives on the chopping block in a re-power even if it were with new gassers.

Don't assume that Velvet Drives will both rotate the same way. My engines both rotate clockwise. My props counter-rotate. The VDs do the work.

You just need to check to see what VDs you have.

 

[rslifkin]

Don't assume that Velvet Drives will both rotate the same way. My engines both rotate clockwise. My props counter-rotate. The VDs do the work.

You just need to check to see what VDs you have.

Velvet Drive CR2s can counter rotate (as can the modern Velvet Drive 5000), but if they're the standard (fairly common) 71C or 72C, they don't counter rotate. They can be configured for either engine rotation, but output will be the same as input (except for one gear ratio I think, where output is always opposite). But the CR2 or the new stuff is the only way you'll get a Velvet Drive where you can choose which way the output spins.

Mine specifically are 2.57 reduction 72Cs, so no counter rotation available (my engines counter rotate). Of course, in a diesel repower, unless using diesels that rev close to 4000 rpm, I'd have to go to taller reduction gears to keep enough shaft speed (otherwise I'd need bigger props than I have clearance for).

 

[timb7734]

Repower

Twenty years ago on Lake Erie my dock neighbor re powered a Chris Craft 41 from big block Mercs to Yanmar diesels. Lower operating RPM meant lower top speed, but this was an SD hull with a full keel, yet the 11 or 12 knot cruise was attainable at less than 2/3 the fuel. That engine did not require shaft or prop changes, just some new gauges and fuel tanks. I believe the conversion was done for &60K.

 

[koliver]

Velvet Drive CR2s can counter rotate (as can the modern Velvet Drive 5000), but if they're the standard (fairly common) 71C or 72C, they don't counter rotate. They can be configured for either engine rotation, but output will be the same as input (except for one gear ratio I think, where output is always opposite). But the CR2 or the new stuff is the only way you'll get a Velvet Drive where you can choose which way the output spins.

Mine are 71C and 71CR. One has the output with the same direction as the input, the other, reverses rotation. One is 1:1.91 reduction, the other is 1: 2.1 reduction.
Point being, builders find the transmissions that works for their boat and engine choice, resulting in counter-rotating props.

 

[Al]

Okay forum, here is a prime example of what I was intending in a fantasy conversion project.. over time as engine/gears come available on Craigslist or some such , find two of the same, like a couple of inexpesive older Perkins or Westerbeke in the 58-85 hp range.

Acquire nice larger accommodations, and travel at a sedate modest 6-7 knots at a modest DYI cost.

https://seattle.craigslist.org/sno/boa/d/everett-36ft-uniflite/7022809377.html

Regards,
Al-Ketchikan

 

[Carl Martin]

How about a couple of Honda BFP 60s. Very efficient, reliable & quiet and at around $7,000 a piece pretty cost effective. Have a swim platform with motor mounts fabricated for a couple of grand & you're just about done.

 

[ranger58sb]

Okay forum, here is a prime example of what I was intending in a fantasy conversion project.. over time as engine/gears come available on Craigslist or some such , find two of the same, like a couple of inexpesive older Perkins or Westerbeke in the 58-85 hp range.

Acquire nice larger accommodations, and travel at a sedate modest 6-7 knots at a modest DYI cost.

In that particular example, and assuming it comes with the two (new?) 440 HO gassers he mentions, maybe it'd be most cost effective to just replace originals with those, then cruise at 6-7 kts on gas.

??

-Chris

 

[Phyrcooler]

Resale time....

Install knock-off Chinese branded motors and you’ll not only have to worry about resale value.... but short of giving it away, even finding a buyer may be difficult. And if economy is down when you find yourself needing to sell, scores of “normally” outfitted boats will make yours impossible to move. While we tend to brush off that “someday”, when it hits you - expected or unexpectedly, a boat can suddenly become a huge weight. JMHO/YMMV

GOOD LUCK whatever you decide

 

[Simi 60]

There will be a big hassle getting any parts outside of China.

Maybe, maybe not.

I get parts from Cummins China faster and for a fraction of the cost of Cummins Australia via alibaba
I used to get parts for a Chinese motorcycle direct as well using a website called taobao

But surely, in that size range, good 2nd hand B3.3 or similar would be available?

 

[Al]

How about a couple of Honda BFP 60s. Very efficient, reliable & quiet and at around $7,000 a piece pretty cost effective. Have a swim platform with motor mounts fabricated for a couple of grand & you're just about done.

Now I like your way of thinking, There are several such combo's around Ketchikan. Perhaps not to the size of 36 feet plus. The overlook to this soluition was the thinking of using existing engione beds, perhaps gear boxes, electrical systems where fitable, and the safety of diesel over gas. However, the concept would surely warrent a view when the cost and time are computed.
Thanks, good post

 

[Nomad Willy]

What’s a Honda BFP 60?
Outboards ???

 

[JohnHayden549]

I am looking for some sort of modern "best practices" wiring diagram for twin diesel, 45 ft trawler, 2 house batteries and 2 starting batteries. I am having trouble trying to understand and trouble the current system, old and somewhat messed up. Current system has a single cranking battery and 2 household bats. Does the forum have a best practices guide for modern wiring?

 

[hollywood8118]

I am looking for some sort of modern "best practices" wiring diagram for twin diesel, 45 ft trawler, 2 house batteries and 2 starting batteries. I am having trouble trying to understand and trouble the current system, old and somewhat messed up. Current system has a single cranking battery and 2 household bats. Does the forum have a best practices guide for modern wiring?

Buy Nigel Calders book, its all there.



https://www.amazon.com/Boatowners-Mechanical-Electrical-Manual-4/dp/0071790330



It is priceless for a new boat owner.
HOLLYWOOD

 

[Nomad Willy]

How about a couple of Honda BFP 60s. Very efficient, reliable & quiet and at around $7,000 a piece pretty cost effective. Have a swim platform with motor mounts fabricated for a couple of grand & you're just about done.

I see you are talking about outboards.
IMO installed as you imply the props are too small, too shallow and too far aft.

 

[Carl Martin]

I see you are talking about outboards.
IMO installed as you imply the props are too small, too shallow and too far aft.

To address your concerns the BFP 60s come with a larger lower unit & prop plus a longer shaft. Moved away from the centerline it should be easy to get the props well below the bottom of the transom. Want more speed? Just install bigger motors! As with everything on boats there are trade offs & compromises to this but it is certainly a cost effective way to repower a boat and much safer than gas inboards because the motors are outside of the boat.

 

[sbu22]

The pics are of a 40 or so footer in Gulfport, MS. I've never been able to catch the owner to discuss. His marina neighbor says it was done a few years ago after suffering a major powerplant casulty. I'm surprised at the minimal "aft rake" - there must have been some reballasting done. Further, although it doesn't show well in the pictures, the swim step is a major and stout fabrication - I'd like to see how it's attached to the hull. The engines are twin 350s.

 

[sbu22]

Lets try this again.

 

[Carl Martin]

Lets try this again.

The outboards appear to be installed with jack plates which are brackets that can be raised or lowered. Actually a pretty good idea for this application. We went on a large Endeavor PowerCat at the St Pete Boat Show last year that was outboard powered and MJM now has a 53 with outboards. Their going on bigger & bigger boats every year. Takes some getting used to but there are a lot of advantages to getting the motors outside of the hull. Safer, quieter, cheaper, simpler to replace & frees up a lot of space in the boat.

 

[sbu22]

Carl - off the subject, but a sister ship to yours is in my marina. I was not familiar with the Scout, then got a tour from the owner just a couple of weeks ago. Lovely boat.

 

[Carl Martin]

Carl - off the subject, but a sister ship to yours is in my marina. I was not familiar with the Scout, then got a tour from the owner just a couple of weeks ago. Lovely boat.

Thanks!