Tohatsu Sail Pro 6hp - Alternator wiring

[Hardhead]

I just bought a Tohatsu Sail Pro 6hp, which comes with a "5 amp" alternator-

Does anyone happen to know the existing wire size of the alternator male-female bullet connectors?

This is where the 2 (positive & negative) alternator wires exit the motor, and are intended to be "plugged in" to the battery wiring.

The existing alternator bullet connector wiring, coming out of the motor, appears it might be about 14 or 16 gauge --- and I'm trying to find corresponding bullet connectors to mate them with the 12 gauge wiring I have leading to the boat battery.

It seems I might possibly have to add a 3rd wiring gauge in between, to help bridge the gap, as none of the bullet connectors I’m finding for sale on-line handle a step up between 14 (or 16) and 12 gauge. There doesn’t seem to be enough extra wiring length coming from the motor to cut the existing connectors and finagle them into 10-12 gauge bullet connectors on the motor end.

Has anyone else ever faced this before? I’m not the brightest guy in the world when it comes to wiring…

As far as the motor itself – it looks great – but I’m still setting it up, and haven’t had a chance to put it in the water yet. Thanks for any help at all-

 

[justsomeguy]

Just a thought:
Can you splice on some extra 14-16 wire from inside the motor cowling so you'll have enough wire outside to triple or quadruple-fold the 14-16 to fit a 10-12 gauge connector?

 

[Leeward Rail]

The wiring on my new sailpro appears to be 18 gauge.
That makes sense, since 18 AWG is good for up to 20 feet long running 12 volts @ 6 Amps.
20 feet should more than reach your battery.

16 AWG is good for 25 feet at that output, if you need to run the cable that far.

12 gauge is overkill for 6A@12 Volts.
And the Sailpro would have to run at full throttle to even get the 5A output is supposedly will produce.

Don't confuse the cable size needed for supplying power FROM the battery to your lights/electronics etc., with the small cable size needed to simply feed the low amp output from the sailpro to the battery.

 

[Leeward Rail]

Also.. normal bullet connectors are far from waterproof.
The connectors that come on both the Sailpro outboard, and the supplied cable, are designed to be "somewhat" waterproof.

If you want to the use the same connectors, I'd simply contact Tohatsu, or your dealer, and find out who supplied them.

I currently will be using the supplied cable (andconnectors), spliced to some 18 AWG Ancor Marine grade cable, to make it long enough to reach the battery. Eventually I'll be installing a regulator so that the Tohatsu's generator cannot overcharge a fully charged battery, and switching to some type of waterproof connectors.

 

[Hardhead]

This is a great forum - thanks everyone. I agree on the gauge not needing to be that heavy - I just happen to have 50 feet of 12 gauge, and none of anything else. I re-positioned two batteries to a cradle under the v-berth, so it's about a 25 foot run, so that was also part of my thinking, but I agree it is overkill

That's a good point about the regulator. I thought I had heard the 2017 Sail Pro was regulated, changing for 2017, but I'm not real confident on that. The manual has almost no information at all about the alternator. I have a solar panel to keep the batteries topped off (hopefully), and if the motors not regulated - that could potentially be a problem.

Thanks again to everyone-
Mike

 

[Leeward Rail]

I thought I had heard the 2017 Sail Pro was regulated, changing for 2017, but I'm not real confident on that.

I called Tohatsu's USA tech support a week or so ago, and they confirmed it was NOT regulated.

I also have a solar panel which I hope to install this week. I have a Solar Charge controller with a digital readout to monitor the battery.
I'm looking into using a regulator from a lawn tractor for the outboard.

 

[Hardhead]

I'm looking into using a regulator from a lawn tractor for the outboard.

I guess I'll have to look at that too. Do you have any specific lawn tractor regulator in mind yet?

 

[Benny17441]

I don't think a 5A charging current needs to be regulated. In real life the alternator output will be significantly less than the rated output and the battery can handle that. As far as the bullet connectors use the correct size to match the engine and the gauge of wire they were designed to accept in order to fabricate a short harness then connect it to the 12 Gauge wire for the long round trip run to the battery. Those alternators were designed for a direct connect to navigation lights in dinghies and fishing skiffs so do not expect any significant contribution to battery charge from it.

 

[Jacktar]

The tohatsu sail pro alternator has a voltage regulator, you can tell by putting a load on the battery and running the engine and checking the voltage across the terminals. Also there are available heat butt connectors that step up or down from 16-18 to 14 gauge wire. My internal wiring from the alternator goes to terminal block and attaches to an existing 8 gauge wire harness that used to connect a second battery in the stern to the battery switch in the midship bilge area at the volcano. I get no measurable loss from the block to the switch as a result. All wiring to lights etc except existing wiring from bilge pump and transducer for depth gunge are 14 gauge which matches the original size use in production of the boat.

 

[Hardhead]

Thanks everyone - I really appreciate the advice.

Thinking further, even if the Sail Pro alternator turns out not to be regulated, and I have fully charged batteries, I'll generally always be running a depth finder along with the motor, so the net charge to the battery will be dang close to zero anyway-

 

[Leeward Rail]

The tohatsu sail pro alternator has a voltage regulator

Interesting... Both my dealer and Tohatsu USA said it doesn't. I'll test things once I get it all (solar + outboard) hooked up. Be interesting to see the actual numbers.

 

[Rusty Keel]

A little off topic but I've been considering the Tohatsu sail pro. Could you, or anyone else for that matter let us know how far/long you can run on the internal fuel tank. I think its about 1 liter. I currently have a 3gal tank. The smallest I can find and still get concerned about stale fuel. I only really motor in and out of the marina. One liter of fuel I don't have to mix with oil sounds perfect but I did want some feedback from someone that's actually used it.

 

[Leeward Rail]

The Tohatsu Sailpro comes with an external tank with a capacity of 12 litres/3.2 US Gal.
(The MFS6CD Model comes with a 0.29 USG/1.1 litre internal tank, has a shorter shaft, lacks the high thrust prop, alternator, etc.)

@Gene Neill would be able to give you run time info since he has had his for a while and used it in various conditions.
If I remember correctly, people have had 11 hours running time on a 12 litre tank ? but don't quote me on that.

 

[Gene Neill]

It's really hard to quantify. I'm still trying to compile some hard data on it. Fuel consumption varies really dramatically based on boat speed, wind, waves, and current. 11 hours on 3.2 gallons does sound totally doable though, in perfectly calm conditions. Go slow.

But get some contrary weather, and it's an entirely different story. That's the part I'm not as sure about, mileage or time wise. Only that the boat sucks gas WAY faster ... in scientific terms.

 

[Jacktar]

I have a sail pro with the 3 gal remote, it sips gas even at pretty good throttle, around 1/2 at 5 knots. As he says it can go up in rough water or strong current but still much less than any outboard for the HP that I have used. If you go with the remote tank the advantage is being able to switch to a second tank if needed. Redundancy is your buddy on the water as you know. I use the 6 gal main tank on long trips with a 3 gal spare just in case. I hate to buy gas at marinas at their prices and this lets me buy ethanol free gas at under 3 bucks a gal at a gas station. Just call me frugal.

 

[Rusty Keel]

Thanks for the input. If I pull the trigger an buy one I'll probably stick with to a remote tank. If I'm not mixing oil in it I can dump it in the truck or mower if its getting a little old. I just have no where to use old 2 cycle gas except maybe burning brush.

 

[Leeward Rail]

I just have no where to use old 2 cycle gas except maybe burning brush.

2 cycle fuel is great to use in any F150 with a triton v8, they burn oil anyhow so you can't tell. With luck it helps loosen the spark plugs so they can come out without breaking. jk

 

[Rltgold]

Looking for a clean way to run the cable from the motor into the boat . Anyone with photos of how they did theirs would be appreciated. Thanks

 

[AaronD]

...Also there are available heat butt connectors that step up or down from 16-18 to 14 gauge wire...

Heat shrink step down butt connectors: https://shop.sailboatowners.com/prod.php?2514/Step-Down+Butt+Splice. The normal ranges are 10-12 (yellow), 14-16 (blue), and 18-22 (red). You can get yellow-blue and blue-red step-down connectors (they'll be marked with a ring or color to show which end is which). More reliable than folding over smaller wires into a larger crimp connector. With apologies to our hosts, I've also gotten them at eBay (in smaller quantities, as it'll be awhile before I go through 50).

 

[Johnb]

Don't forget a fuse AT THE BATTERY END.