Powercat with Outboards

[Mr_reality]

What is everyone’s opinion on the new endeavor powercat with the outboard option. I really like this concept and it seems to address several of the shortcomings of cat engine placement. Do you think this design would adversely affect the handling or rough water capabilities? Love to hear everyone’s thoughts.

https://www.passagemaker.com/cruiser-reviews/the-silent-treatment

 

[DavidM]

I read the referenced Passagemaker article and was intrigued. I too am tired of crawling around greasy engine rooms to do maintenance on inboard diesels.

Four cycle EFI outboards have come a long ways and rival inboard gassers for fuel economy. And you save tens of thousands with two outboards vs two inboard diesels of similar horsepower, much less opening up lots of space in the hulls where inboard diesels would have resided.

I think handling and sea keeping will be fine with the outboards. My only concern would be boarding seas from the stern while going slow, that could swamp the air intakes. Kick it up to 12 kts and that problem should disappear.

Don't believe the article where it says that the outboards have the same fuel economy as diesel inboards at slow speeds. Their fuel consumption table disproves that BS statement, showing 4.7 gph at 7 kts. Most similar diesel trawler cats will use 3-4 gph at that speed.

But for coastal cruising where you are only going to be using it for 100-200 hours a year, a pair of outboards makes great sense.

David

 

[Genecop]

I was on one at a boat show, might have been a trawlerfest..We spoke to the owners at length and they loved dual outboards..The couple where doing the Loop and maybe the Bahamas.

Probably a good option for that type of use. For myself I think the inboard Yanmars That Endeavour uses would be a better fit..Justified or not I feel like it would be safer in certain sea conditions...

 

[Woodland Hills]

The fellow who sold me my Hatteras has moved to a 50’ or so Endevour cat with twin OBs. Last I heard he was in St Pete area shaking his new boat down before going cruising. IIRC, he has a pair of 350 Yamahas.

 

[wwestman]

Arrowcat also makes a 42 with twin outboards. Take a look at what they have.
www.arrowcat.com

 

[LN-RTP]

Tried it once, but a smaller cat: Got a brand new Glacier Bay 2770 January 2016.
Although the boat was ok for Inshore waters like Biscayne Bay, it rocked and rolled too much for me during 2 Gulf Stream crossings and a few trips off the coast.
The 2 Yamaha F150 Outboards was ridiculously expensive to maintain: $1,500.00 every 100 hours for mandatory service by the Yamaha dealer.
Ran it 18 months and sold it, was lucky, buyer fell in love with the boat and paid more for it used than I paid new. (Still in shock..)
First and last brand new boat, way too many things needing repairs and adjustment under warranty, dealer was good about it however, and Yamaha was good about it, hat off to both, but the quality control was missing.
Yeah, different class Catamaran, but it cured me.

 

[Hobo]

Some Reviews

There are these
https://boatmags.com/boat-review-prowler-10-8/

Both around 2010

This one
https://www.boatsales.com.au/editorial/details/argus-e35-displacement-cat-18519/

Then this
Roger Hill Yacht Design, Catamaran, Yacht, Power, Sail, Naval Architect, Catamaran Design, Auckland, New Zealand

Seen a couple of the top one Prowlers for sale second hand 2004 & 2008 years.

Regards George

 

[Scratchnsaw]

I read the referenced Passagemaker article and was intrigued. I too am tired of crawling around greasy engine rooms to do maintenance on inboard diesels.

Four cycle EFI outboards have come a long ways and rival inboard gassers for fuel economy. And you save tens of thousands with two outboards vs two inboard diesels of similar horsepower, much less opening up lots of space in the hulls where inboard diesels would have resided.

I think handling and sea keeping will be fine with the outboards. My only concern would be boarding seas from the stern while going slow, that could swamp the air intakes. Kick it up to 12 kts and that problem should disappear.

Don't believe the article where it says that the outboards have the same fuel economy as diesel inboards at slow speeds. Their fuel consumption table disproves that BS statement, showing 4.7 gph at 7 kts. Most similar diesel trawler cats will use 3-4 gph at that speed.

But for coastal cruising where you are only going to be using it for 100-200 hours a year, a pair of outboards makes great sense.

David

Well that depends on the boat. I get approx. 1.1 gph at 7 mph. with a single 115 on my hull.

 

[mcarthur]

Four cycle EFI outboards have come a long ways and rival inboard gassers for fuel economy. And you save tens of thousands with two outboards vs two inboard diesels of similar horsepower, much less opening up lots of space in the hulls where inboard diesels would have resided.
…
Don't believe the article where it says that the outboards have the same fuel economy as diesel inboards at slow speeds. Their fuel consumption table disproves that BS statement, showing 4.7 gph at 7 kts. Most similar diesel trawler cats will use 3-4 gph at that speed.

As we're talking power cats here, I will assume the limitation on hull speed isn't there or at least isn't nearly as low (depends who you talk to!).

if you're right - that EFI outboards are comparable/better consumption than diesels for higher speed but not low - then matching some EFI outboards with electric may be perfect. The electric handles the <7kn, the petrol outboards handle 8-25kn. Unfortunately, since the outboards typically don't handle large alternators like a diesel genset, that would mean either a large battery bank or a separate diesel genset and a different fuel type.