35 Duffy

trial

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Joined
Jul 16, 2012
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12
Sure looks like the same boat. Came across it on yuckworld searching for 31's.
 

AL.M

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Feb 27, 2020
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22
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7
Age
54
Interesting that the owner claims 16knt @ 2000rpm = 1gpm. The C9 burns 24gph at 2000rpm C9 is rated for 2500rpm with 26gph. Something does not add up
 

powderpro

Captain
Joined
Dec 3, 2011
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3,448
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2,951
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The Ocean
Website
www.oneilboats.com
Boat Make
O'Neil
Interesting that the owner claims 16knt @ 2000rpm = 1gpm. The C9 burns 24gph at 2000rpm C9 is rated for 2500rpm with 26gph. Something does not add up
You are looking at the wrong fuel curve. For the 510hp C9, 2,000rpm is around 13 gph. If the engine is burning 16ph at 2,000rpm, it could indicate it's a little over propped. The ad also says wot is 2,400rpm, but the engine is a 2,500rpm engine, so that's another indication it could be a little over propped. You can't go by what an ad says because they usually have errors, so the boat may not be over propped. But based off those numbers, the first thing I would check is if the engine can hit rated rpm (2,500). Nice looking boat, can't beat a 35' Duffy.


Screenshot (77).png
 

Blitzen

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Sep 1, 2011
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Sumday Isle, RI
Boat Make
Flowers Boat Works 46, 1991 Boston Whaler Outrage 19
Interesting that the owner claims 16knt @ 2000rpm = 1gpm. The C9 burns 24gph at 2000rpm C9 is rated for 2500rpm with 26gph. Something does not add up
Whoa you are way off. My C9 at 575HP prop demand was 28.5 GPH WOT and at 2000RPM was 16-18 gph.
 
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southshore30

Senior Member
Joined
Feb 22, 2012
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198
Location
Cape Cod,MA
Boat Make
Calvin Beal/Southshore 30
Shouldn’t a 35 cruise faster than that with 510hp? 19knts? My friends with a 420 3126 does about that.
 

joe4852

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Nov 22, 2016
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agree. And given there were 350+ built You would think they would come up more often.
 

Hammer Slammer

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Joined
Sep 7, 2011
Posts
386
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169
Location
Plymouth, ma
Boat Make
31 Duffy
That’s a great boat. My buddy had that built by Andy , the bounty hunter is its sister ship. Congratulations to the new owner you will love it.
 

Aloop

Senior Member
Joined
Jan 24, 2013
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212
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26
That’s a great boat. My buddy had that built by Andy , the bounty hunter is its sister ship. Congratulations to the new owner you will love it.
If that was the Albert H, I got a tour of it 2 or 3 weeks after taking it to Plymouth
 
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