Tohatsu Sail Pro 6hp - Alternator wiring

Aug 22, 2017
1,609
Hunter 26.5 West Palm Beach
It was my understanding that, on a lot of charging systems, you were supposed to NOT fuse the wire from the charger to the battery, for fear of frying the rectifier/regulator if the fuse blew. It always seemed like a risky proposition to me, but that is what I have seen specified on many different motors. I do not know about the Tohatsu specifically. I don't know if ABYC has a requirement.

As for unregulated charging systems on outboards, my experience comes from older Johhny/rude 2-strokes. A 6-amp charger on one of those was enough to jack up the battery voltage over 16vdc, destroying electronics & cooking the battery, if you didn't turn on enough lights & other accessories to use up the amps. Usually a well charged group 27 battery would be OK for half an hour or an hour before the voltage started to clime into the danger zone. A bow light, a stern light, a VHF, a FM radio & a depth finder were not enough to use all 6 amps. More than once, I have been known to drift with all lights & radios on while waiting for the battery voltage to drop, so that I would feel safe starting the motor back up. CDI makes the aftermarket retrofit regulated-rectifiers that I used to replace the original unregulated rectifiers on my old OMC motors. http://www.cdielectronics.com/wp-content/uploads/2013/09/IS-193-3408.pdf

My 3.5-hp Tohatsu 4-stroke burns the entire contents of the 1-liter tank in about half an hour if I push it hard. It will easily last 3 times that long if I take it easy. I wish that I had a larger external tank for it.
 
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Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
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
My boat already a metal fitting from a previous motor when I bought it.

I made the existing hole bigger for the oem supplied cable, potted the hole with epoxy, installed the cable with sealant around it, and reinstalled the metal fitting.

I left enough cable hanging outside to allow full up/down/left/right movement of the motor.
All the fitting seems to be designed to do, is protect rain from getting in.

If it fails, I'll likely swap it out to a round cable with a "cable clam" /cable outlet with a built in gasket seal.
https://shop.sailboatowners.com/cat.php?6277

Here's a shot from when I bought the boat. You can just see the old cut cable sticking out.

2015-04-11 13.31.50.jpg
 
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Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
you were supposed to NOT fuse the wire from the charger to the battery, for fear of frying the rectifier/regulator if the fuse blew. It always seemed like a risky proposition to me, but that is what I have seen specified on many different motors. I do not know about the Tohatsu specifically. I don't know if ABYC has a requirement.
I called Pisces Marine, the Tohatsu dealer where I bought my Sailpro, and they said that the system is protected. You can connect/disconnect the wire on their small outboards with the charging system with no problem.

In fact it has a fuse built in.
There is a risk of damage by reversing the polarity, which is why they use male & female connectors at the end of the cable. The system will try protect itself even then, but it's better to simply wire it in such a way as to prevent it from ever happening.
 
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Apr 11, 2017
571
Catalina C22 Solomon's Island, MD
I'd like to drill a hole in the transom, to run the battery cable though like shown above, but I'm a little leery of drilling holes in the transom. Is that how most C22's are set up? I might decide to take the plunge, it would make it a lot cleaner.

On a different issue, how do most of you route the fuel line into the gas lazarette?
 
Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
Fuel line on the new designs is run like Gene's Photo above. The fuel primer bulb on the external tank that came with my tohatsu is a tight fit, but it works.

Why are you worried about drilling a hole in the transom ?
@Gene Neill solution would work great if you don't want to do that.

I assume he has some type of connections behind the access cover so that the cover can be fully removed easily, if not it's only a slightly longer run to the factory battery location where the wires would end anyhow.
(FWIW: if you haven't upgraded your gundgeons/pintles that cover is what you need to install, to make that possible. I did that so I could upgrade to the ruddercraft kickup rudder)

I plan on eventually moving my battery to under the v-berth so that is part of my decision making, so any future plans you have, may help narrow down your choice.
 
Sep 14, 2014
1,251
Catalina 22 Pensacola, Florida
On my C 22 the fuel line and alternator run out of the lazarette thru the aft vent for the compartment as in pix, also I put a piece of window screen in each vent to keep out wasps not run off by my old sock with 3 moth balls in it tossed into both stern compartments and the v berth area.
renew vent cowl and repalce hoses below .jpg
 
Mar 2, 2018
232
Catalina Wing Keel San Diego
Thanks for the tips. I don't like having the electrical and gas next to each other though.
 
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Sep 14, 2014
1,251
Catalina 22 Pensacola, Florida
12 volts, no exposed wires and no gas fumes in vent because that is what they are designed to remove. And plus no new holes in boat, yeah team!
 
Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
@Rltgold... Gene's routing for the fuel line itself, is what the factory intended on the later C22 models.

I agree.... there is a minor risk with having both fuel and 12V in the same routing.
That said, with regular inspections it shouldn't be a problem. Especially if you run the wiring through a hose or wire loom to minimise any chafing where it exits.
The cable supplied by Tohatsu has external tubing already.

In my case, the 12VDC cable is sealed in the hole in the transom, and has a external sheathing.

I'd suggest inspecting gear regularly. Doing it every time you go out is ideal, but realistically it won't happen. :doh:

@Jacktar I'd be worried that if you ever ran into the rare problem of having that boat on it's side... a lot of water would be pouring in those vents.

That said, being an older model you don't have the luxury of the fuel locker that the later models have.
Some pre 1987 model C22 owners have made a fuel locker that sits at the aft end of the cockpit. That way there is no fuel inside the boat, with it's attendant risks of leaks or fumes.

Anyone else with an older C22 have a different way of routing the outboard alternator wiring ? (or fuel lines)
 
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Apr 11, 2017
571
Catalina C22 Solomon's Island, MD
Thanks to everyone who posted photos. It's good to see different set-ups-
 
Sep 14, 2014
1,251
Catalina 22 Pensacola, Florida
By the way the more interesting thing is the search for the oil drain plug for the crankcase on the tohatsu sama!
 
May 16, 2020
8
Ranger 20 Spokane
Hello,
I just bought a new Tohatsu 6HP Sailpro for my Ranger 20. I have charger on the boat that has various modes and allows me to plug into normal 120v. The wires from the charger come out the back of the boat and are connected to what looks like the female end of a plug the connected to the previous outboard. Well, I wasn't thinking when I sold the other outboard and I sent the other half of that plug with it, since it was connected. I'd like to just replace the plug now. What suggestions do you have for a waterproof plug to connect to the engine? I need a plug because I take the motor off pretty frequently as well as every time I trailer the boat.

Thank you
 
Sep 14, 2014
1,251
Catalina 22 Pensacola, Florida
The sail pro comes with a pigtail connector for the alternator to battery that already has a sort of quick disconnect pair of male female plugs just at the outboard itself. I connect that directly to the house battery not through any charger. less resistance for the max 13.6 volt charge from the motor (based on motors built in regulator detecting need for that voltage) and no chance of a ac charger system doing something weird to the outboard.
 
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