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Duffy Electric boats....?

Discussion in 'Tenders & Dinghies' started by Norseman, Sep 18, 2013.

  1. Susanrisa

    Susanrisa New Member

    Joined:
    Jun 23, 2017
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    Location:
    Virginia
    Hoping to find some help.

    I have a 2004 21 Classic and although batteries are fully charged. I am not getting any power. Converter box starts when I plus in shore power but the indicator lights stopped lighting up. Infraspeed box has no lights at all anymore. No power at helm either.

    Everything was working fine last weekend, not sure if anyone else has ever run into this.

    I checked all fuses and wiring connections, voltage meter is showing 0 when I connect to motor.

    Any help appreciated.

    Thanks,
    Susan
  2. Norseman

    Norseman Senior Member

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    Hi Susan.
    Sounds like the controller is fried. (But it could be a bunch of other stuff too)
    Do you have the Italian controller mentioned earlier in this thread?
    Do you leave the boat plugged in to shore power with the charger connected?
    Do you have a surge protector on the circuit?

    I had the same problem twice, it was the controller both times.
    Retail is $1,6K from Duffy.
    Read this thread, I think much of the problems and solutions has been mentioned.
  3. Susanrisa

    Susanrisa New Member

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    Thank you.

    I will check the controller. Just to make sure, you are talking about the black box under the helm, not the converter or infraspeed box, correct?

    Thanks,
    Susan
  4. Norseman

    Norseman Senior Member

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    Not sure what the converter or infraspeed box is?
    My boat had two boxes behind the helm seat: A battery charger and a speed controller. They both were protected by plastic boxes with computer case fans for ventilation.
    Sounds like your boat is different with stuff under the helm.
    If the boat has been plugged in and if there was a power surge in the neighborhood, all the boxes may have fried:(
    Happened to me, the surge (https://en.m.wikipedia.org/wiki/Voltage_spike)
    killed the boat, TV and stereo in the house as well as a battery charger on a sailboat on my dock.
    Pretty common in Florida.
    Guess it is unheard of in California as Duffy recommends we leave the boats plugged in all the time:(
    (I have since installed multiple surge protectors, but that is like closing the barn door after the horse has ran away)
  5. Hardcraber

    Hardcraber New Member

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    Virginia
    Hi, I came across this thread and joined the forum to see if I could offer a bit of help. I have a Duffy Newporter, 2003 model, and just experienced the same problems you are having. I was not getting power to the console, but the charger was working properly.

    I found the techs at Duffy to be extremely helpful. First thing they had me do was to test the voltage going to the key switch to see if power is getting to the key. I had no power coming to the switch.

    Then they had me test each cell of each battery with a hydrometer. Evidently if one battery or one cell is weak there is a relay that will not operate. My batteries passed that test.

    Next step was to get 12v to the key switch to ensure the problem is not in the console. You can either run 12v from another 12v battery, or isolate the last 4 batteries from your battery bank (assuming 16 x 6 volt batteries) to get 12 volts. I did this and got power back to the console. Everything operated as it should.

    After a few more tests, my problem was that the converter had failed. The converter takes 48 volts from your battery bank and converts to 12v to feed the console (lights, stereo, bilge, refridge, horn etc).

    I've ordered a new converter from Amazon, should be here today, and I'll finish it up this weekend.

    Hope this helps. Again, I found the folks at Duffy to be extremely helpful. I texted pictures, and they would call back with things to test and check.

    Good luck!
  6. Norseman

    Norseman Senior Member

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    Good job, congrats.
  7. worldsense

    worldsense New Member

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    SouthernCA
    I've been following this thread for a while now with interest. I've picked up an older 1984 Duffy, original built by Shock Boats. It has the old 2-speed, 5 position switch, and 2 strings of 3 6V batteries.

    The boat needs some TLC, but is actually in pretty good working order. Unfortunately the previous owner didn't spend much time taking care of during the ~12 months he owned it. The batteries were a bit low on water, and none of the electrical accessories worked except the running lights. Most of this is little/"fun stuff".

    However, being a power boater and otherwise technical geek, I'm more interested in getting the boat to a baseline functional level.

    To that end, when I look at the wiring I find it a bit difficult to mentally untangle in my head. The two strings of 3 batteries appear to be individual wired to the switch/throttle, which I assume is how the two speeds are powered - either 18V in low-speed, or 36V in high-speed.

    In the interest of diagnosing the system/power consumption, I've tried hooking up a power/shunt-based Ammeter to the negative of the port side battery string, with positive coming from either the "first" battery in that string, or the first battery in the starboard sting. In the former case I am able to get a reading for power consumption in forward. In reverse, measuring from the port battery string only I get zero current at all.

    A few questions to get me started, any input is very much appreciated:

    • I know Duffy doesn't publish a schematic, but I'm curious if anyone has made an attempt on the older (pre-variable speed controller) Duffy's to document the electrical system at any level?
    • If not a full diagram can anyone explain the primary purpose/wiring of the rectifiers?
    • Is it typical/normal for the 36V charger to be wired (+/-) to two batteries on the starboard side? If so how does this affect charging/balance for the port side?
    • Am I correct in assuming that one set of batteries is preferred, in that it is used consistently for low-speed forward? Leaving the other set less used, and potentially overcharged since the two strings will have had different usage over any given outing?
    • Is it safe to assume that the 12V power for the lights, stereo, cigarette lighter is essentially stolen from 2 batteries on the port side? Is this worth resolving with a 18V/36V DC -> 12DV converter?
    • Since the accessibility for the throttle switch is so poor, I've been hesitant to try and take that all apart, but perhaps that's the best solution barring any other?
    Sorry for the long intro-post, just trying to get my bearings straight (pun-intended) before dealing with some of the more cosmetic, and mechanical issues - although I think the belt(s) maybe next.

    Happy Friday to All!
  8. Norseman

    Norseman Senior Member

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    Duffy emailed me a wiring diagram, call and ask 'em.
  9. joules

    joules New Member

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    Location:
    southern USA
    Hi Worldsense, welcome and congratulations on your Duffy. I have a 1983 pop-top kinda like yours. I had a GE/Taylor Dunn 36V shunt motor (still have actually).

    The control switch, I believe is supposed to rewire the battery bank from 6 series 1 parallel to 3 series 2 parallel but mine wouldn't do this, it would only discharge from 3 of the 6 batteries when running in low.

    on 18V I would see 25A (450W) discharge rate which gets me about 3.5mph, and on 36V high at 50A (1800W) I would see 6mph.

    I replaced the electric motor and switch with a Thunderstruck EV 6hp saildrive kit with the optional Curtis 134 directional pot-box. Best upgrade ever. 6mph came at 1200W now, with "Infraspeed" like control but with an even quieter brushless motor. I had to upgrade to 48V to support this kit, so now I am sporting 10kWh of batteries. I also put in a small 12V battery and a 48V to 13.8V converter, a battery balancing system, and 8 digital volt-meters to monitor each battery.

    I too use the shunt based watt hour meter, it works pretty well and is an unbeatable tool for the price. The bargain shunt meters can't read reverse current flow, so you can't see charging. I am waiting for the Victron BMV-712 to come to the US, this high end model performs a Peukert calculation to indicate your real battery levels.

    I never figured out if the series/parallel switchover system was faulty or if it just used three batteries by design. Duffy really couldn't answer any electrical questions about this boat, but the rest I get pretty decent support. It is a perplexing problem, but if you want to keep the switchover system we could probably figure it out. There are two diodes, and reversing is achieved by changing the polarity of the field winding/stator winding (the smaller set of wires on the motor that do not connect to the brushes).

    Whenever you have to deal with registration, make certain you use W.D. Schock as the boat manufacturer, and Newport Electric Packet 18 as the model. My state gave me hell about the prior boat registration incorrectly listing Duffy as the manufacturer.

    On to your questions:

  10. joules

    joules New Member

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    Hey Norseman: Question for you. You said much earlier that there are derelict Duffys in canals somewhere in the Ft Lauderdale area? Is there a large collection? I am still searching for an aft rail chock and may make a trip to FL soon. Any leads or pointers?
  11. Norseman

    Norseman Senior Member

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    Nah, not a large collection.
    I have seen a few, 4 I think, but 3 are gone now.
    Keep checking Craig's List or eBay.
    Sold my Duffy almost 2 years ago and have not paid attention lately.
    Should never have sold it, finally got it 100%, new batteries and all, then I got New Boat Fever and had to go out and do something stupid. (And expensive)
  12. Jim robertson

    Jim robertson New Member

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    I have a 2008 16 foot Classic Duffy with power rudder. The boat seems to make a little noise at a very low speed. It is like a ticking or my daughter says a rumbling but not bad. I would appreciate any ideas on what this could be.
  13. Fishtigua

    Fishtigua Senior Member

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  14. Flyinbob

    Flyinbob New Member

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    Honolulu Hi
    The early Duffy power rudders were under designed and the gearing in the rudder that transfers the drive from the vertical mounted motor to the horizontally set propeller shaft had some problems after a while.
    Replacing the power rudder is the only fix if it gets bad but a little noise is nothing to be concerned about.
  15. Flyinbob

    Flyinbob New Member

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  16. Capt Ralph

    Capt Ralph Senior Member

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    Now, install a pair of 400hp engines.......
    This battery stuff will never make a dent into real marine sales.
    I wish all designers well & luck but real world burns diesel,, quickly.
  17. Capt J

    Capt J Senior Member

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    I have run the Dasher a few times. It's a heck of a lot faster than the duffy! Has an 85 mile range at the duffy's 6 mph. You can charge it on 1 50amp cord, it just takes longer. With 2 50 amps you can charge it in under 4 hours. The price is over $400k so I've heard. It will do 30-35 mph.
  18. Jim robertson

    Jim robertson New Member

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    Purchased a 2007 16 foot Duffy. The actuator stopped working. I called Duffy technicians. they said the only help is with the Duffy factory. I called the factory. I was told to send the actuator and controller for testing. I sent them $50. Postage. The factory called and said they no longer had the equipment to test these parts and I needed to purchase a new motor, controller and actuator. All work together and must be purchased together. Just under $3,000. Not a happy camper.
  19. 2002Duffy18

    2002Duffy18 Guest

    Jim, see my recent post about rebuilding the "Infaspeed" actuator. It's simple to test and repair if necessary, assuming you have the same component as me.
  20. USNmullett

    USNmullett Guest


    Been in the boating industry about 17 years, last 10 of which primarily on the West Coast. Specialize in electric propulsion and worked for Duffy for half a decade plus 2 other major electric boat manufacturers. There's issues with manufacturing and quality control we could talk about for days but the guy (Pier Urathane) who used to make the props for Duffy sold them to the public until his unexpected death and now the kids tossed the molds. Tried to buy them. Few people have tested different props being 1 small 3 blade SS and 2 urathane ones that I know of and was given a report of after. All 3 caused overheating issues with the controller (Curtis platform with stainless case put together by Duffy). The **** boats are so finicky I just use the standard ones floating around Newport. If I hear of any alternative I'll let you know.
    If you ever need any parts feel free to reach out. I source just about everything for the models dating back to Shock / Duffy colaberation. They claim a lot of parts are proprietary, more so just sourced from local mom and pop shops locally.
    Eden
    [email deleted]
    Last edited by a moderator: Jan 12, 2018