Piver 31 with 46 mast

Discussion in 'Multihulls' started by DennisRB, Jun 7, 2010.

  1. DennisRB
    Joined: Sep 2004
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    DennisRB Senior Member

    My mate wants to put a 46 foot mast on his 31 foot piver. It has a 33 foot mast on it now and wont go without 20K winds. It has an ancient 20hp yanmar diesel engine that weighs around 400-600kg. The idea being decent light air performance in tropics. Is this mast and rig going to be too big?
     
  2. catsketcher
    Joined: Mar 2006
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    catsketcher Senior Member

    Really dumb

    Pivers were a little under canvassed but going to 46ft is silly and he will probably find himself upside down. Best and cheapest thing is to get rid of weight. Take everything off the boat and clean out every locker. Get rid of the diesel and the folding prop - I hope its a folding prop. If not then that is the problem. A yammie 9.9 is ideal for this sized tri. If he wants extra sail area then go down to the mono sailors and ask for an old lightweight number one for a reacher and put it on a furler. The learn to sail properly - Pivers like "Rage" and Mangrove Charlie were pretty quick in their day. Now they are old and heavy with bad sails and heavy engines - give the boat a chance.

    I have a 46ft mast on my 38ft cat - it is too big for a Nimble or AA31.

    cheers
     
  3. DennisRB
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    DennisRB Senior Member

    haha. Thats what I was thinking. The mast is 10m now. The rig and sails was donated from an old mono. I think 12 would be max. Its just that 14 meter masts seem to come up often for some reason. The boat has a 9.9 yammie AND a 20 yanmar. It does 4-5K with the outboard and 7+ with the yanmar. It has a big fixed blade prop. I would think a 10hp diesel would have been OK and should do 5k. The thing is the boat was pretty much empty already. Its only going to get heavier with cruising gear.
     
  4. catsketcher
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    catsketcher Senior Member

    get rid of the prop and fix the rig

    The prop is slowing the boat hugely. If you get the diesel and prop out and sell them they will help buy some nice new sails. My mums 32ft cat was real dog with twin fixed props. When she got a new main and folding props her cat was a different boat.

    Keeping the motor and props is a huge mistake. The Yammie will go faster with the prop and diesel gone. It sounds like the guy who put the diesel in did not have the correct philosophy for cruising a tri - keep it light. Get some nice sails - a new main and some second hand jibs, give her a bottom job and she will go nicely. My little 24ft Piver could really fly but she had nice sails and was light. Your mate should give the boat a chance by equipping it as it was meant to be.

    cheers

    Phil
     
  5. DennisRB
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    DennisRB Senior Member

    Thanks for the advice. I really cant see him loosing the diesel. He loves it. The thing is out of the boat ATM and if it were me i would try it without it. We moved the boat from Sydney to Yamba which was at a bad time as we had either no wind or northerlies. The diesel let us down when oil supply line blew to the head. We used the $500 extra extra long shaft outboard to motor and motorsail it most of the way. It got us there in the end but it was slow. It never popped out of the water even in a gale. The thing my mate hates is no maneuverability with the outboard as there is no rudder behind it. Its a dog to dock. I guess some clever engineering would have the outboard hooked to the steering, also the alternator on the yanmar is good to charge the batteries.

    After the Yanmar blew my mate then spent hours and $$$ on it to fix the head, so I would say he will be reluctant to get rid of it. What would an ancient yanmar 20hp be worth?

    What sort of performance increase would we get by removing the yanmar and prop under sail and under power from the existing outboard? If the outboard cant do 5K+ cruise its no good. Also nothing is as annoying as the sound of an outboard. At least its a 4 stroke. However if the boat sails well again we won't need to use the damn thing! :D
     
  6. cavalier mk2
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    cavalier mk2 Senior Member

    He should comfortably cruise at 5 1/2 - 6 knots with the diesel and shaft/prop out of there. I saw a bit bigger piver that used an outboard well to great effect. Piver reportedly liked wells and they do let you pretend its a inboard. He should also sail off wind twice as fast as he is now at least with that thing removed.
     
  7. catsketcher
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    catsketcher Senior Member

    Get rid of the lead!

    This going round and round a bit. To be truthful your mate will get the worst of both worlds unless he starts thinking like a tri sailor. Light, light, light. A 20hp diesel is the dumbest thing to put in a Nimble or AA31. A modern Yamaha 9.9 should get the thing up to hull speed with lots of grunt to spare. As for noise - I don't get it. A modern 4 stroke outboard is quieter than any diesel.

    The best way to mount the outboard is on a sled. The link below shows Jim Brown's own Searunner 31 with its sled. To give some background he used to cruise with his family on board with a 4 horse outboard. This was enough in calms. I think your mate needs to get rid of the motor for a while as he seems to rely on it way too much.

    http://www.searunner.org/scrimshaw/photos/photo11.html

    The Nimble should sail well in anything over 8 knots. The heavy diesel on such a boat is terrible, the prop an abomination. Your mate is going about this all wrong - make the boat sail first and THEN get a donk. He is starting the whole thing as a motorboater would.

    cheers

    Phil
     
  8. DennisRB
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    DennisRB Senior Member

    Cavalier. I think the boat had an outboard well and they closed it up and fitted the diesel. I guess it pays to do research first.

    Phil. The current outboard is an extra long shaft with extensions (just checked pics its a Mariner 9.9). It cost $500 used and has electric start and forward controls. The sled is interesting but the current one has just been mounted off a dropped mount and due to its extra long length never pops out or goes under water. The prob is steering under power at close quarters.

    Here are some pics of the motor attachment and sailing. Yes the boat looks like a heap of **** but the point of that trip was to get it to a location where it could be hauled and worked on. Its sitting at Yamba now slowing getting restored. I'm sure the hard dodger isn't the best for windage, but I was glad we had it when we got caught in a gale on xmas eve.
     

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  9. catsketcher
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    catsketcher Senior Member

    get a tape measure out

    I think the boat is a Pi 34 and not an AA31 or Nimble. I think the boat used to be at Toronto in Lake Macquarie. Still my 38ft cat with heaps more windage does really well with a single 25hp outboard. The Mariner will probably not have the prop to push like the Yammie.
     

  10. DennisRB
    Joined: Sep 2004
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    DennisRB Senior Member

    Yeah it was at Toronro. We sailed it up to Yamba last Christmas. I was told it was 31 foot. I guess we need to get out the measuring tape.
     
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