Duffy Electric boats....?

Finally got new batteries and ran the Duffy for 2 hours this past weekend. No problems so far. I am having trouble figuring out a way to charge (6) 6v batteries with a 3 bank 12v charger. My set up is 2 banks of 3 batteries making 2 banks of 18v. Each bank is wired in series.

Now its all about getting some hardware fixed. My surrey top is tweaked pretty bad. Some of the pole mounts are not correct or the right angle/degree. Anyone know where I would go about finding these pieces of hardware?

Can somebody tell me what this is and why I need it?

A lesson in how NOT to wire a boat?

Looks like an isolation diode setup but has several things wrong.
1. Using aluminum as a conducting material (leads going to aluminum angle should use a large ring terminal and be connected to the diode post itself not the angle)
2. Crimped ring in foreground not heat shrinked and loose wire strand out of connector.
3. Connection on wire labeled "10" very sloppily taped and of dubious method (ie. bolt?)

Those style diodes have a soldered-only connection method on that end, a better method would be soldering the main wire and heat shrinking it without a secondary connection. With any soldered connection, proper support very close to the connection is also recommended to keep vibration from cracking the harder solder joint.

That automotive fuse below also should be in a waterproof or at least splash resistant boot, it will last much longer that way.

Thanks for the info. I bought the boat like this. Although it seems to run fine, I want to correct the wiring and make it safe. Any idea what diodes I need to buy to upgrade this mess?

That would be hard to do without a lot more info; size, amperage capacity, voltage, type etc.. There are literally thousands of diodes available on the market, picking out the most suitable would depend on what function they're being used for. Most marine applications using larger ones like that are for charging circuits (from alternators or generators) to multiple battery banks and the diodes are used to isolate the banks while charging. More "modern" systems use ACR's (Automatic Charging Relays) but I doubt your Duffy is set up with that.

Well to start with, I have:
(6) 6v batteries
36 volt GE motor
Salzer rotary switch (low-high forward reverse)

I use a triple bank marine charger which connects straight to the batteries.

So my question is, Do I even need the diodes at all?

It was the prop ! I rounded the edges where before I had filed them more to a point. Put her back in and 90% of the noise , that sound just like belt squael, is GONE. It's getting dam near perfect!

Without a schematic of the installation I really can't say unfortunately.

Aren't there lots of 36 volt battery chargers for golf carts? Not exactly Marine. but a battery charger none-the-less

I need some help with my 1990, 20 ft. Duffy. While running some new battery cables, there was a short across a tool after which the boat would only go full speed in forward or reverse. Tried a new "black box". No help. Suspect the console mounted thingy with the handle (throttle?). Where to get a replacement? How to test? Thoughts?

That was quick!! Thanks. I am assuming that that since the switch part, forward and reverse, is working properly, it is a rheostat issue. I saw your earlier post about the rheostat part. What is the HIN?

Some further information. Here are some photos:

the boat



the handle


the black box


the switch



Am I correct in assuming that the rheostat in the switch part is 12v and that the 12v "signal" is sent to the black box and converted to 36v for the motor?
Given that the switch does forward and reverse functions and there is no speed control, does it seem likely that the problem is in the switch apparatus or should I also suspect the controller (black box)?