Wiring a 14' aluminum boat w 15hp 4 stroke

[SCK]

Hello ,
i`m wiring up old 14` Lowe Boat w 15hp - Need advise on how to layout and wire up Boat . Battery will sit mid ship under the centre row Bench . with a Voltage Meter and RPM/Hour run Meter beside it . Also will mount a small electrical panel 6 switches w fuses and a dc cigarette lighter mounted on the side of the Bench about 2 ft away . I have a special Cable I order , which supposedly runs from my Honda Motor & has a rectifier / regulator to keep the Battery charged , but not sure where it should wire into . The 6 switches I would dedicate to the bilge pump/Nav.Lights / Cigarette Receptical / Fish Finder/ Voltage Gauge/ RPM Gauge. Does this sound normal ? Where is a good place to ground the Battery to and how long or what size cable do you recommend ? The rest of the wiring, what size should I use . Where should I wire in the Cable from Motor/rectifier/regulator ? and do I put a main red shut-off switch to disconnect the whole system if needed ? Whats your take on solar panels & chargers ? Is it worth it or is an on board charging system better. Any information /diagram layout would be greatly appreciated !
THANKS in advance.

 

[Silvertip]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

You start with a plan, otherwise you end up with a bunch of poorly routed wires and a system that is more trouble than it's worth. It seems that everyone that wants to wire/rewire a boat wants to go "switch happy". Understand that devices that have their own power switch do not need another separate switch. Radios, GPS, fish finders are just a couple examples. What you need to do is go to a dealer and look at how a tiller steered boat is configured for gauges and other electrics. They almost always have a small panel on the port side of the boat on the rear bench. Thats the way you face when operating a tiller steered boat. The battery can be anywhere. You run two 10 gauge wires (black-ground, and red-+12v) to the fuse panel through a circuit breaker or fuse at the battery. Everything else branches off the fuse panel to the accessories. Keeping the battery charged is why you are installing the charging kit. Keep in mind, just because you have charging capability does not mean the small alternator on this engine is capabable of fully charging a deeply discharged battery in a 10 minute run back to the dock. You would need a solar panel nearly the size of your boat to be used as a "charger". Small solar panels are simply battery maintainers. Go to the top of this forum and look at the Generic Boat Wiring Diagram. Eliminate what you don't need and use what you need. How you run the wires is up to you. The charging wires (hot and ground) from the engine need to connect directly to the battery.

 

[Splat]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

Yea what he said. But also all your ground wires need to be ran back to the battery or to a grounding block then from there back to the battery. Do not ground anything including the battery to the matel if the boat. This could lead to galvanic corrosion and big problems.

Bill

 

[flargin]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

Y all your ground wires need to be ran back to the battery or to a grounding block then from there back to the battery.
Bill

I agree with that..

Do not ground anything including the battery to the matel if the boat. This could lead to galvanic corrosion and big problems.
Bill

Really? I thought all services should be grounded to the hull (batteries + generators etc) of metal boats?

 

[Silvertip]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

Once the charging system is added to the motor, the motor will very likely end up being the ground to the hull anyway. Using the hull of the boat as a conductor (completing the circuit return leg) is different than bonding the electrical system.

 

[flargin]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

Once the charging system is added to the motor, the motor will very likely end up being the ground to the hull anyway. Using the hull of the boat as a conductor (completing the circuit return leg) is different than bonding the electrical system.

Thanks, that makes sense... I agree not using the hull as a conductor, but I was really confused about not bonding to the hull. Thanks for the clarity.

 

[SCK]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

I`ve opted to go solar as opposed to charging the battery through the Motor.
Anyone have any experience with them . The reg./rectifier to charge the battery for this Motor is no longer available , so I`m giving this a try .
All my wires will be 10 gauge . As for the grounding , I`m not sure I understanding the grounding bit. I get that you shouldn`t ground directly to the metal on the aluminum boat . I`ve got all the negative wires running back to the battery, So where due i ground the "-" battery terminal to ? Or do I ? Do i run a ground wire to the Motor ? and where on the Motor ?

 

[Silvertip]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

And how big a solar panel is this you are planning to use? 10 gauge wires is way overkill. Nearly every circuit on a boat can get by with 16 gauge wire provided you don't run high current draw items from it. Radios, lights, locators, GPS and similar stuff can all use 16 gauge. Trolling motors (depending on size) would require anything from 10 to 6 gauge. Ground on your boat is the negative terminal of the battery. The only ground you need for the engine is the battery cable from the negative terminal on the battery to the engine block. It doesn't matter where on the engine block since it's all one big blog of metal.

Just so you know, unless the boat sits for at least a week between uses, a small solar panel would take at least that long to bring a battery back up to snuff if the engine charging system is not working. Small solar panels are at best a battery maintainer, meaning they will keep a battery topped off provided they are fully charged to start with or just slightly discharged. A solar panel big enough to be called a charger would set you back Hundreds and would not include the charge controller.

 

[SCK]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

So if I understand this correctly , if I run a 8 gauge wire from the neg terminal on the battery , to the frame on the Motor , I should be good ? I still don`t understand why I have to wire it to the Motor , because if I ground to the Motor , isnt the Motor touch the Boat , thus grounding to the boat , which you don`t want ?

I also need to know how big of a fuse , I would need for the whole electrical system . Any ideas how i would figure that out ?
Also what size do i fuse the following at Fish finder / naviation lights / bilge pump / cig. lighter rec. / voltage & rpm gauge
I`m also running a cig. receptical to charge the battery . So I need to have this receptical wired into a curcuit breaker before going directly to the battery ? Please let me know !

 

[Silvertip]

Re: Wiring a 14' aluminum boat w 15hp 4 stroke

Grounding on your category of boat means things are connected to a single point and that single point is the negative terminal of the battery. If your engine is electric start, you need a separate cable from the positive and negative post of the battery to the engine to run the starter. If you don't have electric start, then there is no reason to ground the engine. And again, 8 gauge wire is not large enough to run the starter on the engine. It will get hot and melt. 8 gauge wire (two of them -- one black, and one red) run to the fuse panel to power the panel and provide a ground bus for connection of accessories. Your engine is not the central ground point for this installation. The negative terminal of the battery is the central ground point. The power distribution point for the boat begins at the positive battery terminal. The fuse panel merely serves as the branch point and circuit protection point for all other circuits.