Best source of electrical wiring basics for pontoon/boat?

Radarcontact

Cadet
Joined
Sep 23, 2011
Messages
26
I bought a pontoon fixer-upper. I can do the fab and resto work np but I don’t know 2-strokes and I’m not confident about the electrical.

i have a pretty good understanding of basic electrical, I.e. I’ve installed plenty of car stereos, etc. but I’m starting from scratch here:
- 2 batteries (one motor)
- battery switch (Perko basic)

I’m gonna have to wire to the motor at least, but would eventually like to install some basic gauges and possibly some lights and a stereo of some sort.

Looking for a good source of info that I can study and try to learn what I need to.

Thanks.
// Radar //
 

HotTommy

Lieutenant Junior Grade
Joined
Mar 15, 2013
Messages
1,025
My contribution is a big picture look at your electrical system. This may not be exactly right for every boat, but I think it describes most older boats that would be running a 2-cycle engine.
  • Battery #1’s primary purpose is to provide electrical power to the starter and engine ignition system to crank and get the engine running.
    • For that there is one large cable from each battery post going directly to the engine near or at the starter
    • There are also smaller wires going to the ignition switch (likely at the throttle quadrant) and from there to the engine to activate the starter and ignition system when needed
      • These wires may go directly from the battery or may be in a wiring harness between the engine and throttle quadrant
  • When the engine is running, magnets on the spinning flywheel pass by a stator device and this produces alternating current.
    • Most of the engine and boat systems require direct current, so there will be a rectifier/regulator on the engine to convert the alternating current to direct current at a voltage the system can handle (e.g., 12.5 to 14 volts)
    • This power goes to run the engine and recharge Battery #1
  • Battery #2 is typically there to power accessories (e.g., trolling motor) without running Battery #1 down (leaving you unable to restart the engine)
  • The Perko switch is there to allow Battery #2 to be electrically disconnected from Battery #1 when the engine is not running, and to be connected when the engine is running to recharge Battery #2
    • Some Perko switches do this automatically and other require the user to manually switch between connected and disconnected
  • Accessories such as gauges, lights, audio and trolling motors may receive power either through the ignition switch or directly from either battery.
    • Gauges are typically wired to receive power when the ignition switch is on
    • Lights, audio and trolling motors are typically wired directly to a battery with one or more switches controlling them
      • For example, there may be a single ACCESSORIES switch that allows power to go to additional switches for AUDIO, RUNNING LIGHTS, etc.

Wiring your boat safely and properly requires that you understand enough about volts, amps and watts to choose the equipment, wires and connectors appropriate for your application. Failure to understand this and do the job correctly may result in damaged equipment, premature system failure, or even worse ELECTRICAL FIRE from overheated parts. Be careful! And good luck with your project.
 

ahicks

Captain
Joined
Sep 16, 2013
Messages
3,957
Nicely done Tommy. I hope people appreciate the time and thought behind a response like that....

I would add that there will be should be 2 electrical sides to battery #1. There is the engine side, which powers not only the ign. and starter, but all of the ENGINE gauges and warning lights (eg tach. and tilt gauge) as well as the choke and power trim and tilt. These will be supplied by wiring (usually factory built harnesses) leading from the engine and running off of fuses located on the engine - all powered from the main battery cable from the battery to the engine.

The second side of batt. #1 (boat side) is about nav. lights, pumps, accessories and other gauges (e.g. battery voltage, gas gauge, etc). This power is best run from a battery buss/fuse panel installed under the dash, with one positive (fused at the battery) and negative wires coming from the battery to supply power to just the fuse panel.

There's a lot more to this (like the reason you might want to have a #2 battery, and commonly used color codes), just adding a few thoughts to Tommy's notes above. -Al
 
Last edited:

Rich1950

Cadet
Joined
Feb 26, 2020
Messages
10
If you are going to go with two batteries....a house and a start....I really would recommend the BlueSeas Add A Battery kit. This kit is far superior to the basic switches YOU have to deal with. It comes with an Automatic Charging Relay component that senses when either or both of the batteries need charging and takes care of it without you doing a thing.
Plus, it is really a simple system to put in. You cannot get much more plug and play than this.
There are two kits, one for alternators up to 65 amps and one for alternators up to 120 amps.
If you decide to go that way, I have installed one on my boat and would be glad to answer any questions.
 

Radarcontact

Cadet
Joined
Sep 23, 2011
Messages
26
Well! Wow, thank you all for the great info.

Achris / Chris - more like a few weeks... lol. Thanks for the link, will check that out later on tonight

Tommy - YES, thank you for taking the time to write such a great response! Much appreciated

Ahicks - I found a wiring diagram for the Perko on their site, so that’s pretty simple, except it refers to the Starter going to Common on the switch and the negatives both connected to the Engine Ground. So at this infancy level of this project and my limited understanding of outboards I’m not even sure what those are referring to! I will figure that out though, not a problem, I’m sure.

Scott - I wasn’t aware of that section but that’s my next stop. Love those stickies. Thanks!

Rich - thanks, but I’m gonna keep the Perko for now but I’ll look that up and bookmark it for any “phase two” improvements once I’m done getting her “healed up” from my mass disassembly and reconstruction. Right now we are bust rebuilding fencing from scratch just using the old aluminum frames but new foam and aluminum “skins”. Be done and ready to move forward in a few days.

All - My boat came with the Perko hooked up, the motor able to run, and a set of hodge-pudge gauges and switches with no wiring attached. Lights with no wiring. But that’s fine because I can’t live with that (OCD about things needing to match). But I will need to install whatever new ones I buy, obviously.

Near where I grew up, there’s (was?) a place (in Melbourne Florida) that is a giant store with nothing but boat stuff that was bought from manufacturers as they changed model years (?). Boxes of new (and a lot of used stuff too) gauges, seats, hardware, etc. Unfortunately it 8 hours from where I now live so I can’t go there, but I really wish I could for this project! Gonna check to see if they have a website, but doubt they could even catalogue all the stuff they have and be able to put it online for purchase. But I’ll check for sure.

Found a few interesting books on Amazon about boat electrical wiring. Hopefully I’ll find the right one to have as a reference as I go along.

Much respect to all.
// Radar //
 
Top