Converting a 33.5 from sailing yacht to trawler...

May 7, 2020
3
Hunter 33.5 varies
I'm buying a Hunter 33.5 that has been de-masted which is fine by me as I intend to use her as a trawler to do the great loop. I'm not yet at the boat, but doing research and planning. One of the big changes will be to add a 3 (or 4) blade prop. To that end, I'm wondering if any owners can tell me which transmission reduction ratio was used on the 1995 33.5? It looks like it'll be either 2.36, 2.61 or 3.2 to one. I've looked in all the normal spots and am not seeing any data available - including the owner's manual...
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
Welcome aboard, @sandiegoskipper .

Showing my ignorance here, but, wouldn't transmission reduction ratio be in the motor specifications and not the yacht specifications? Do you know what kind of motor is currently in the boat? Or, do you have plans to change out the motor for something a little bigger?
 
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May 7, 2020
3
Hunter 33.5 varies
Welcome aboard, @sandiegoskipper .

Showing my ignorance here, but, wouldn't transmission reduction ratio be in the motor specifications and not the yacht specifications? Do you know what kind of motor is currently in the boat? Or, do you have plans to change out the motor for something a little bigger?
Hi Marine - thank you for all that you guys do! The Yanmar engine is a 3GM30f, however, the trans is bolted to the engine and built by someone else - not Yanmar. The final drive gears can vary depending on the designer's specs, boat weight, use, etc.
 
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Dec 14, 2003
1,393
Hunter 34 Lake of Two Mountains, QC, Can
The transmission on that engine is generally a Yanmar made Kanzaki model KM3P or KM3A. There is a plate on the tranny which will give you the details. As Dave said, the reduction is 2.62 (or 2.61). My 34 with the 3GM30F has that tranny coupled to a 1-inch shaft. My prop is 3-blade RH 15 X 11. Max RPM is 3400. With my shoal draft, hull speed is 7.1. I cruise at roughly 2750 RPM and get 6.5 knots (calm wind, no current). Hope this helps. Good luck.
 

Johnb

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Jan 22, 2008
1,419
Hunter 37-cutter Richmond CA
I have been told that the motion of sailboats without masts is horribly rapid, anyone know more?
 
Feb 22, 2011
71
Hunter Legend 37 Muskegon, MI
Don't want to rain on your parade but I'd buy a trawler (twin screw) rather than a "broken" sailboat and trying to turn it into a trawler. You'll have more room, more tankage (Water, Fuel, and Waste), longer range, and as JohnB suggests, possbily more stability. Plus you'll avoid all the "What happened to your mast" comments. Good deals can be found on older trawler style boats and if it is for live aboard purposes, other than just the "Great Loop", see more room above. Don't stick yourself with something that no one else would want (for resale), unless you're getting it for close to nothing. I know someone will jump in my s**t (I don't really care) for being critical about your choice but use this as a continuation of your thought process. If you're thinking of the Great Loop I'm thinking of and you are from SD, you'll have to get the boat there by transport, which isn't really cheap from California. If the goal is the loop, you might want to shop in the Great Lakes area or somewhere in the east to save the transportation expense of getting there. OOps, sorry, I just checked and see that you indicated TN for your location. Good luck on your endeavor and don't forget, a bad day on a boat is better than a good day at work. Safe travels.
Dave
 
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SFS

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Aug 18, 2015
2,065
Currently Boatless Okinawa
Can't believe I am going to recommend a stinkpotter, but I agree with Dstegs. With the economy in the shape it is in, boats are going to become even less expensive in the very near future, and something like a fast trawler would get you there a little faster than that 33.5 and with MUCH more comfort, but with a very manageable fuel burn (in a single screw diesel). The loop takes a while, even if you do it non-stop. The creature comforts in a trawler would matter a lot I would think.

Edit: Don't know about boats in TN, but one popular starting point in early spring is the Gulf Coast. There are likely tons of boats in places like New Orleans, Mobile, Pensacola, etc. Just like with sailboats, look for ones owned by people who had your same goal, but plans changed for one of a million reasons.
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
Ditto DStegs49 and SFS..............having owned a number of power boats from 21 - 56 feet. A small trawler or a large cuddy cabin power boat, even with a single engine offer a lot of cockpit comfort and living accommodation.
 
Oct 22, 2014
20,989
CAL 35 Cruiser #21 moored EVERETT WA
Buying a sailboat to do the Great Loop is a question unto it self. The question asked by the PO was answered by Dave.
 
Nov 26, 2012
1,653
Hunter 34 Berkeley
Kanzaki transmission. A three blade prop is going to get you your best motoring power. Your boat choice may not be the best but I understand you may not have a choice. A powered sailboat will us a lot of fuel and go slow and will not go in shallow water. Also, much less maneuverable.
 

SFS

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Aug 18, 2015
2,065
Currently Boatless Okinawa
And if you are serious about changing the prop, I've heard really good things about Campbell Sailor props. It's a Canadian firm, and they have their own take on designing propeller blades.
 
Jul 1, 1998
3,062
Hunter Legend 35 Poulsbo/Semiahmoo WA
The keel is 4,500 lbs, and I believe it is lead. should be worth something for scrap. Removing that much weight will raise the waterline and reduce drag but will still need something to protect the prop and rudder. The rudder will have to be shortened a lot.
Remove the pedestal, move the helm forward, and go with a different kind of steering mechanism?
On another note, with the low coachroof, coming up with a pleasing wheelhouse design will be crucial. What concepts do you have to share? Something Nauticat style?
From the specs, hull speed is 7.2 kts so that's about it, after that the horsepower req'd really goes up.
 

Johnb

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Jan 22, 2008
1,419
Hunter 37-cutter Richmond CA
That seems counter intuitive.
No, the momentum of the mast slows down the response of the boat, especially noticeable for beam on motion. Without the mast the boat is over stabilized and the motion becomes uncomfortable. I have some experience of this on my previous 23 ft with the mast down.
 
May 21, 2017
16
Allmand 31 31 Lake Superior
My two cents: I owned one of these boats, a 1992. Great sailing boat with plenty of room down below. Sad to think of one of these boats without a mast. Was lucky enough to place second in the cruising class with this boat in the 2011 Transuperior Race, like I said, a great sailing boat.
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
Now that the topic has been taken care of, what if, and this is a big what if, what if the new owner where to put stabilizers fins at the bottom of the keel to keep the boat's roll to a minimum?
 
Feb 22, 2011
71
Hunter Legend 37 Muskegon, MI
Along the line of thought that John N. put forth as far a removing the keel. I would think that with the relatively round hull, the boat would be quite unstable and I would imagine could turn turtle quite rapidly.
 
Jul 1, 1998
3,062
Hunter Legend 35 Poulsbo/Semiahmoo WA
Along the line of thought that John N. put forth as far a removing the keel. I would think that with the relatively round hull, the boat would be quite unstable and I would imagine could turn turtle quite rapidly.
Very good point!
Especially if one went with a Nauticat-style wheelhouse and loaded the topsides up with gear (solar, dingy, and consider windage, etc.). The concept will obviously need some serious design calculations.
Using large windows isn't the most seaworthy design. There was a local Seattle boat salesman who went with his dad down the coast in a Nautical and somewhere between Oregon and Cape Mendocino large waves broke through the windows and the boat sunk in a short time. Fortunately they were rescued by the Coast Guard and lived to tell their story.

Seems many do-it-yourself-projects take years to finish, at least those I've heard about. The time of one's life is worth something and there is no round trip. Plan B: Find a single-engine trawler already built, do the trip, then sell it when finished. Plus points: Waste a minimum amount of (life) time and should be able to sell it (maybe not in the home state) at not a whole lot less than what it cost, but definitely less loss than the Plan A project boat option.

Getting insurance on the Plan A project option will surly be more expensive.