Installing dual batteries on a boat

[@garrydye2394]

I like how the beer bottles are adding up as the video gets longer. Well done.

[@rickdemaria3737]

Dangar!.....THANK YOU....I'm a new boat owner of a Macgregor 26X in Connecticut, USA. Great video. Understandable for a novice like me! Pilot by career and Sailor for love of the water......I love your videos...You made another knowledgable sailor!!

[@garethbarker9498]

Hard to believe this is the third time in 3 days you’ve come to my rescue mate 😂…rectifier then steering now battery setup.. you are some fella Thanks again Stu

[@DangarMarine]

Welcome!

[@Jaaaap]

I love your chalk board. It just clarifies it so well!

[@MikeTLive]

Your diagrams and thought process is more important in many respects than your execution. We all don’t have your boat so will have different execution. The theory and thought, however, will be much more aligned. Keep right on with the pictures and process. Thanks again for all the videos!

[@DangarMarine]

Thanks mate. I have always felt that teaching the theory is more important than giving a quick explanation that people can copy. As you say, everyone's situation is different and understanding helps people adjust for that.

[@boulahya05]

you are the best sir , even a universty teacher dont explain electricity like you do , thank you verry verry much mister dangar

[@DangarMarine]

Thanks mate, glad to hear the videos have been helping you. :)

[@rantube104]

Love your channel and your accent, I like to fuse or use a circuit breaker at the positive post of each battery to protect cable, dual batt. Switch and main fuse block from battery short , high amp draw and smoking hot wires.

[@lauriehaynes3144]

Laurie Haynes very well explained Stu well done

[@motorv8N]

Thanks for another great vid, Stu. And don't ever give up on the chalk board. Very helpful! Have a safe bike trip.

[@DangarMarine]

Thanks mate. Don't worry, I'll keep inflicting my chalkboard on people. ;)

[@Tdawg-2024]

Thanks Stu, used this video to help do my dual battery setup.

[@tonywalker5402]

Another clear concise video with a nice bit of very dry humour. Well done again. I love your videos. THANK YOU.

[@vetterfellow]

Excellent information = how to. I learn something every time I watch this channel. Thanks Bud !!.

[@DangarMarine]

Thanks Angelo! Got your pics safety too so I'll put one in next week's video. :)

[@peterjensen6844]

Yes! I've been waiting for this one. Plan to do this to our boat this coming Spring.

[@DangarMarine]

Nice one Peter, good luck with the job! :)

[@joem8912]

Beautifully explained and demonstrated....well done Stu!!! Best boat videos on KZbin!!!

[@beerturbogarage]

Stu, if you want the alternator to allways charge both, place an electric battery switch between both positives, there are type that will auto click on 13.6 (orwhatever volts) so no mater what battery you have selected, if your motors on you will charge both - just my 2c.

[@DangarMarine]

That certainly sounds like a good way to go. A few people have mentioned using voltage sensitive relays etc so I'll definitely look into tweaking things down the track and maybe doing a follow-up video.

[@beerturbogarage]

www.projecta.com.au/dual-battery-systems-accessories-1/12v-100a-voltage-sensitive-relay i have some thing like this on the car, while charging you charge both, while off they are seperate...so one runs the camping acc while camping, so it can go flat and you still start of the other one....or if your in a situation you can do the over ride to run both to start the car....similar to your manual one, however you cant select only the second battery, like you can............but there no reason why you cant run your setup, with something like this just to activate duel charge.....best of luck and keep up the videos!

[@DangarMarine]

I think I'll grab one of these and have an experiment with it. It certainly looks like it will save a lot of hassle with switching batteries all the time.

[@Cess182sn]

Hi Stu...Thoroughly enjoy your tutorials, detailed but yet simplistic for us common folk. I just wanted to make an observation and I apologies if I'm stating the bleeding obvious, but I noticed you said that if you have a dead battery (lights left on), you would start your motor on the #2 battery, then switch back to #1 to be charged. In this situation you will need to leave it on "both' for a while as the dead battery will not have enough current to excite the alternator. I won't charge. This is one of the downsides of the manual switch unlike the "smart" system which disconnects the battery and prevents it being drained less than 11 volts, it will still retain enough charge to excite the alternator once the motor is started.

[@ronpowell2373]

Cess182N (Cessna 182 owner? ) Unless your outboard is based on a car engine (Honda 4 stroke) and has a belt drive alternator, the engine will charge a dead flat battery, or at least dump current into the battery any way. Outboards tend to use permanent magnet alternators with the magnets being part of the fly wheel mass, so no excitation voltage required or used. This is done for both weight and space reasons. The regulation - if any- is done after rectification . The rectifiers may or may not be part of the regulator, but there is always rectifiers if there is a battery charge circuit available. If the alternator has an out put of less than 8amps there is often no regulator, but 'vented' (old style removable cell caps) batteries have to be used. These system will kill maintenance free batteries pretty quickly as once the battery is charged the charge voltage goes up to 16-17 volts, and so the battery gasses a lot. In the manual for my engine the fix for 'over 15volts on voltmeter' is to turn on your navigation lights! If the engine has a regulator it is series regulator. These work by allowing the voltage to get to some where around 13.8 to 14.2 volts and then if the voltage goes up further the regulator starts sending some of the current through a variable load, there by converting the excess power into heat. This alternator/regulator system is not efficient as the alternator produces full power al the time, even when not required, but they are small, simple, reliable and cheap.

[@Cess182sn]

G'day Ron.. Can I take it by your opening line that a Honda 4 stroke outboard (or similar) will not charge the battery without some voltage from the battery to excite the alternator. Unfortunately not wealthy enough to own a C182.. just hire them

[@DangarMarine]

My little Honda just has fixed magnets, so as Ron says, no current required to excite the alternator like a car or a yacht. He is also right that some larger V4 outboards do have alternators, but we generally work with outboards under about 50HP which are all just permanent magnet regardless of brand.

[@ronpowell2373]

+Cess182sn - separate alternator systems don't usually need an excitation voltage to get going if they have been run before. Even though the soft iron cores are all laminated to stop eddy currents and be quick to change magnetic field strength as required by the regulating system , the core does have some residual magnetism, enough to start a weak power generation that will power up the regulator and kick start things. The armature current really isn't all that big, a 60amp alternator may run 5 amps , usually much less, at full load. I have used a AA 1.5V battery across the field to get an aircraft alternator to kick into life after the alternator had been on the shelf for 10 years (right next to a fluorescent light that had been on all the time , slowly degauzing the alternator with stray 50hz/240volt pulses) That was 28v 100A alternator , so the flat battery/no charge thing is pretty much a non issue. UNLESS your engine is like the newer car engine where the ECU controls the alternator, in which case nothing will work if the battery is under 11 volts. I hope they never bring that idea to boats!

[@eddieself1311]

JayElle prob would

[@rjrombal]

Your video was a fabulous reaffirmation & education on how to perfect my battery switch. Currently, Battery 2 is used strictly for the housekeeping components of my boat & is located under my dashboard. Battery 1 is close to my motor. I'd prefer to move Battery 1 back under the dash, primarily because its 45 pounds makes for an inferior weight distribution. Thanks!

[@DangarMarine]

Hey Rich, weight distribution is an important parts of laying out a small boat, but make sure you have thick enough cables if the run does become longer.

[@darren3604]

Hi Stu. I mounted my battery switch at the helm. I start and run out to sea on battery one and then switch over to battery 2 to run accessories while fishing. I also start and run back home on battery two. This routine keeps both batteries healthy and having the switch at the helm encourages good routine. Cheers.

[@DangarMarine]

Yep, if you don't have to run the cables too far then having the switch at the helm can be a great way to go.

[@iwrenchbluecollar7498]

I prefer to switch the grounds. My battery switch and all my accessories are switched to ground. Love the videos 👍

[@izaacbanks3337]

I wrench blue collar why

[@anonymous_friend]

great sense of humor dude

[@jimbogasoline2042]

Great job Stu! Have fun on you're trip!!

[@DangarMarine]

Thanks Jim!

[@CliveOldfield1]

Nice video. I added a similar switch to mine also. The switch I chose also has the Off-Bat1-Both-Bat2 positions, allowing either to be selected or both in parallel. Answering another post, you *can* change between batteries with the engine running, *provided* you go through the 'Both' position. It had a very strong warning not to totally disconnect the batteries ('Off' position) with the motor running to avoid damage to the charging system.

[@DangarMarine]

Thanks mate. Yes, avoiding the off position is all you really need to do in with a motor "make before break" battery switch.

[@chrisheyer8424]

I wondered how this would work - thanks I've had the switch for about a year sitting around... I'm gonna go hook this up :-)

[@pererikeithunronning9637]

Hi, in Sweden we have a releyswitch, it controls the charging, as soon as battery 1 is charged it switches to battery 2. That means you always have full charged batteries.

[@coopw101]

I think this will be my first project this spring. Thanks for idea the wife will get a charge outa it. Can't be more than 40 bucks.Peace and be safe out there.

[@DangarMarine]

Well worth doing this I reckon.

[@joebenson7385]

Really like they detailed demo’s. Like the pros and cons. Thanks!

[@hoyks1]

Like the projects in my shed. They start with a solid plan, which is modified shortly after beginning. Then I start finding what I'm missing that I was sure was in a box somewhere here ... hen there is a trip to Bunnings/BCF/Jaycar... then I find something that makes the job easier, so I try and incorporate that. So when I'm finished it bares little resemblance to what I started making, or has been thrown in a dark corner of the shed and I'll finish it one day when its on the critical list again.

[@maherkassim9178]

Thank you sooooo much for the chalkboard schematic. 👌👌👌

[@DangarMarine]

Most welcome 😊

[@daveh8686]

Excellent, thank you from Canada!

[@MichaelHenryGomes1]

I'm so stoked you made this video. I was wanting to do this. Now I can. Thanks bro!

[@DangarMarine]

You're welcome Michael. :)

[@Ramshackle6984]

I had to summon my inner Dangar Marine this week out on the water. My boat kept briefly losing power which kills my EFI engine dead in the water and threw all my electronics out of sorts . Long story short I found that my battery switch had gone bad and I had to bypass it. In their infinite wisdom the manufacturer put the switch up under the gunnels under the aft starboard seat which was fun to get at with 95*F sun on your back hanging upside down with a rusty adjustable spanner and a Leatherman. However, it worked and we got back to boating. Ordered a new switch today that can be mounted in a better place. I ordered a very similar switch to the one in the video, just one for a single battery.

[@gellotion]

Great video! Nice simple explanation and Love the humor as well

[@DangarMarine]

Thanks mate. :)

[@deweypug]

This is very good. (Love the beers going!!)

[@sergioabdilla4577]

Gr8, informative and down to basics, with a real world approach and no BS. I was wondering if you could offer some advice as to what gauge wire I should use? I’m rewiring my 5.4 meter glass boat from scratch as I baught it as a project boat with no motor or wiring. I’ve studied a lot on the net to gain knowledge and plan what I’m going to do. But the tables to work out wire gauge seem to be dependant on insulation temp. ratings. ( confusing!) Basically I’m installing a dual battery set up with a dedicated house battery and start battery controlled with the BEP 3 switch assembly ( 2 battery switches, an emergency parallel switch and a DVSR ) What gauge wire would you recommend for my power distribution / battery paralleling. Loads would be typical for a 5ish meter fishing boat . Bludge, live well, deckwash pumps. Nav/ Anchor LEDs. Flood lights LED. Sounder/ plotter VHF radio. Anchor winch . I anticipate putting a brand new motor on it. Besides the motor control/ instrument wiring, are the starter cables from the motor also the alternator output wires to charge the battery?

[@alvin1984fiji]

made more sense the way it was explained and demonstrated rather then showing bunch of circuits..have a columbia mark 2 sailboat 34 footer...same setup as yours...so i should put an additional switch for the house batteries?.and protect the engine parts from damage. wouldnt want my keel to fall off so thinking of putting an anode bar near aft and link all negitive leads to it?

[@rossjackson7134]

Just bought another boat (a project, lol) so this was handy info mate. Thank you. Nice Series One door being restored in the background too.

[@DangarMarine]

Series 1 is almost finished now!

[@rossjackson7134]

Dangar Marine, I’m a Landie Tragic too. Been driving the buggers since 1971, I’ve got it bad. Lol.

[@mikepoint4983]

Yet another fantastic vid keep on truckn good buddy , Cheers

[@DangarMarine]

Thanks, will do!

[@pomarem]

Thx Stu, the boat I bought has a dual battery setup but I wasn't sure how it all worked but know I do😀 cheers

[@DangarMarine]

You're welcome, glad the vid helped you. :)

[@johnnyrogers1199]

Thanks for this video...it has been a great help and I loved the humor!!

[@DangarMarine]

Glad it was helpful!

[@scottm5342]

I see you are in possession of the greatest tool whenever one is working on a boat: Beer. Well done.

[@DangarMarine]

No toolkit should be without six!

[@michaelhefford5649]

Chris asked if you can safely change over batteries when the engines running. I didn't think you could due to arcing. More importantly, that beer on the bench wasn't going down very quick so you may need a stubby holder or get used to warm beer. Great video - thanks.

[@DangarMarine]

Hi Michael, modern battery switches are pretty safe swapping between batteries. I might have to make some Dangar Marine stubby holders one day! ;)

[@Shooting_the_Breeze]

Cool video. Thanks for posting. i know its been up for a while, but i hope you see this to answer my question. Since you have your electronics connected to Battery 1 will they cease to function if you switch over to battery 2 ? I have my radio and fish finder on my single battery, but I would like to add a second battery. Thought is run out to my spot on battery one, kick it over to battery 2 whilst out fishing etc and then probably run back home on both. But if my devices are still connected to Battery 1, would this work ?

[@LawnCareEvolution]

I should really add a second battery to my boat. I do always carry a thumper battery and jumper cables (just in case). But a second battery makes more sense. Great video Stu.

[@DangarMarine]

A booster battery is a good option too. I'm hoping the two battery setup will be more wife friendly though. I'm always getting the call, "The bloody boat won't start again!"

[@TimsWorkshopTJY]

Good one Stu, Enjoy your bike trip. A pause for the cause is always a good thing for perspective. I'm like you only have my one battery hooked up even though my boat came with the battery switch and 2 batteries. I do take 2 batteries with me fully charged. now that I have this video as reference will hook the both up to use the switch like it was intended when I go out in the lake. After my one heavy viewed video it has inspired me to get more serious and make a video log and ideas for more youtube clips. probably never as good as yours but just for fun anyway. Thanks

[@DangarMarine]

Thanks Tim. Sounds well worth hooking those batteries up if you have all the bits. Glad you're enjoying making your vids, I really liked the one on fixing the chainsaw and weed eater.

[@TheVbelanic]

I could tell you were starting to gradually catch a buzz as you were making the video with them random beers thanks for the video

[@DangarMarine]

You're welcome mate. ;)

[@adrienjoinette8913]

Excellent video, a little bit soon for the boat I'm working on but this video will definitely be helpful in a few weeks from now, thanks : )

[@DangarMarine]

You're welcome Adrien. :)

[@JohnVH-diy]

I use two batteries. One for starting only and one for all other lights and accessories. I put a continuous duty three terminal solenoid between the two batteries. This connects the two only when the ignition is on, as when running the motor. This way I can camp overnight with my navigation lights on and use my interior lights and water pump etc and still have a full battery for starting in the morning. Both get charged when the motor is running.

[@Sidicas]

why positives into the switch instead of negatives?

[@cherylmarie3370]

Hi Stu great vid thank you :) any chance you can add to this with a 6 gang panel switch please along with if needed the additional terminal block and negative bus bar setup etc cheers Paul

[@DangarMarine]

Thanks Paul. I'm going to be doing some more wiring on another boat soon so stay tuned!

[@cherylmarie3370]

Will do... looking forward to it!

[@briangay5418]

"If you squint you can imagine that's heat shrink" Love the sense of humor!

[@prins2x]

Thanks! Just bought a boat and looking at adding a 2nd for small things like lights, bilge etc. As I'd only be installing a smaller 2nd battery I'd be installing an isolator/ voltage sensitive relay to keep charging my 2nd whenever the engine is running. Do you think would be ok?

[@Noahlochner0]

Who makes that switch? I clicked the link but it goes to a different one. Cheers!

[@daniellee414]

thanks for the information, I'll be trying it this weekend. looked like a 3 stubbie job.

[@TitanFallDeath666420]

Dangar more Outboard repair vids please!

[@Dietermesker]

Thanks! Just installed it in my RV

[@MiniLuv-1984]

Just wondering if it is common marine practise to just crimp the lugs or crimp then solder the lugs? Want to point out that Stu's switch arrangement is fine for two cranking batteries OR two house batteries, but not for mixed battery arrangements. If one is a cranking battery and the other a house battery, then you should get one of those gizmos that are intended for that purpose, so you don't crank with the house battery and don't run house loads (lights, trolling motors, fridges, radios etc.) off the cranking battery. They are intended for different kinds of loads and either will fail quickly with the wrong kinds of loads.

[@ronpowell2373]

Yes, get a Voltage Sensitive relay for that sort of thing, or better yet go for something like the Redarc Dc to DC battery controller/charger systems- expensive though.

[@MiniLuv-1984]

The redarc kind of solution should be ok Ron. Voltage sensitive relays will cut a battery off at a preset voltage, but will not manage the charge cycle - crank and house batteries have different maximum voltage and current charge characteristics. Maybe getting to complicated from what Stu was discussing (both batteries as crank batteries), but house batteries OTOH are expensive so you don't want to kill them prematurely to save a few bucks on the charging system. If you are going to use a house battery, get the real deal.

[@ronpowell2373]

Benny, deep cycle house batteries of the same or different chemical type to the start battery are no real issue. DC to DC chargers for exactly the scenario you have listed are available and have been tested / used for years now in caravans and 4 wheel drives. The chargers have all the different charge rates/end points/float charge rates in them and you merely select what the battery type is on each out put. This whole 'different house battery type to start battery type' thing is a non issue these days.

[@DangarMarine]

That's interesting Ron. In my case Benny these two batteries really are general purpose batteries designed for small boats that normally only have one battery and small amount of "house" devices like navigation lights. I should do a video on day on a bigger boat like Dave's yacht we did the winch on as he definitely has very specific house and cranking batteries in there.

[@chriswithers4148]

Thanks for a great vid on dual battery setup. I've got the kit but not had time to install it yet. Can you change from batt 1 to 2 while the engine is running?

[@stanpatterson5033]

Good question, I await an answer on this too. Can't see why not. Might be a problem though if you were dealing with huge giant forklift-sized batteries and a charging system that put out hundreds of amps, but then you'd be using much heavier switches anyway. Even so, on the small-scale level we're at with Stu's setup, it makes me wonder how much of a shock (no pun intended) to the electrical system it would be switching on-the-fly, and whether any sensitive devices would suffer from potential surges.

[@thetrejos101]

I don't know if it's right or not, but I have had a boat with this battery setup for 12 years and I switch between the two batteries with the engine running and have not experienced any issues.

[@michaelhickey6141]

Yes you can but don’t turn it off while the engine is running or you will likely damage your alternator

[@gronet75]

If i have a maintainer, how do I keep both connected to it?

[@RonnieTucker1]

You must be psychic! I have all the bits for a second battery install ready to go, but will watch this first before I add mine.

[@DangarMarine]

Good luck Ronnie!

[@camabberfield6020]

Love the chalkboard mate, your vids really help👌🏻👌🏻

[@carfern53]

great video. Question, how do you connect a trickle charger to the batteries?thanks

[@DangarMarine]

Hi Carlos. Trickle chargers are just connected positive to positive, negative to negative on the battery. If you intend to plug your boat into a trickle charger whenever you are not using it I would look into adding the type where you connect a cable to your batteries permanently and then you can just plug the charger into a connector at the other end whenever you park the boat up. The cable with the plug will often come with the trickle charger.

[@JustMike2791]

"I'm sure that'll fade as a memory." That statement rings so true with me as well! HAHAHA

[@carfern53]

Thanks for the prompt reply. With the dual battery switch can both batteries be charged at the same time if the switch is placed for both and I place the trickle charger on one of the batteries or do I charge each one individually? Thanks again, happy holidays and new year.

[@DangarMarine]

You can charge both batteries at the same time with it switched to both (if you wire to the switch), or you can have the charge cable bypass the switch altogether.

[@carfern53]

thanks again

[@googleplusisdead]

Other than not being "normal", would there be any reason you couldn't wire the ground to the switch? That way, no issues if it accidentally got grounded to the aluminum hull. RichE

[@ronpowell2373]

The switches are only single pole (ie, only one contact that changes selection) . If you are asking if you could switch the negative wires of the batteries and have the positives hard wired to each other the answer is yes . There are corrosion, earth loop and earth fault issues that makes switching the positive less problematical for almost every body. Way too much to go into in a reply! But the short answer is yes you can.

[@DangarMarine]

Thanks Ron!

[@Mooff2]

How many charging amps do you see when you let one battery go flat and then switch to both? Do you worry about your wire gauge?

[@chrisrainville976]

Like always,another great and useful video from Stu,and I thank u👏😀🥃👍

[@fishingfool2644]

So you wired your dual batteries exactly how I wired my 16ft Valco bayrunner. To deal with the console electronics and small voltage drains, I also installed a second switch so that I could turn off everything connected to the console panel. That's just a suggestion.

[@DangarMarine]

A second switch is a good option. As always I'm a bit pressed for time so I didn't put a lot of thought of preparation into this install but I think I'll definitely tweak it down the track.

[@courtneylang7477]

I love your videos. I've been watching them nonstop. I've searched youtube and forums for how to wire a tachometer to an outboard. I even bought the repair manual with wiring diagram for my outboard. I must just be dense because I can't figure it out. How many alternator poles do I have? where does the signal come from? Is a voltage regulator the same as rectifier? Lots of stuff on vehicles and motorcycles. Not a lot on outboard motors.

[@ronpowell2373]

Ok, No idea of your specifics because you haven't listed your motor model. But some I can. A rectifier is simply one or more diodes that change the AC from the alternator coils to pulsing DC. There is no control of the voltage from just a rectifier, they just change AC to DC. A regulator takes the uncontrolled pulsing DC from the rectifier and controls the maximum voltage that is applied to the battery- some where between 13.8 and 14.2 volts is typical. So-- your motor that has electric start will always have a rectifier, but may not have a regulator. If your boat has a regulator it will always have a rectifier. The tacho is a simple thing, but the number of ways things are done in boats is what makes things confusing. You have to use a boat tacho, preferably the one recommended by the engine manufacturer for the simplest install. Car tachos typically use the 12v coil ignition pulses from the points, or a 5volt signal from the ECU ( from the crank angle sensor or cam position sensor) . Outboards use the pulsing DC from the rectifier to work out the RPM. Standard wiring loom colours for the tacho are grey or purple. Often the tacho wire is coiled up inside the forward control when it is shipped. How many alternator poles/pulses per rev is totally motor dependant.

[@courtneylang7477]

Hey! Thanks Ron. I didn't list my specifics bc I didn't want to assume anyone would care. I love Danger Stu's videos, and I thought a general educational video on tachometer wiring, functions, and installation might be well-received by his subscribers. Bring the chalk board back, Danger Stu!! Anyway, I have a 2003 60hp classic Mercury 2 stroke. The wiring diagram says it's the Gray wire for signal. It has a stator, but I can't find the number of alternator poles anywhere in the manual. And of course, I don't really know what an alternator pole is or what I'm looking at under the cowling.

[@DangarMarine]

Hey Courtney, as Ron says, much of it is very motor specific unfortunately. If the tacho is general purpose aftermarket then it must be configured with the correct number of cylinders and poles. I'm planning to add a tacho to the Green Machine soon and I'll definitely be filming it.

[@ronpowell2373]

+Courtney - It looks like mercury IDs engine by serial number , not year/hp. I can understand this but it means having to be specific at the owner end. Anyway, the photos for 60hp stators on Marine engine.com show the alternator (about 16Amps max output, so don't fit a big stereo, navaids, nav lights, a ton of cabin lights and expect the battery to charge up! ) to be either 6 or 8 pole, your engine probably uses a regulator with internal rectifiers and so an aftermarket tacho can be tried at 6, 8, 12 or 16 pulses. Just keep switching selections until you get something believable. It does not hurt the tacho to be run on the wrong number of pulses, you just wont get a correct reading. I would also suggest getting one of those small go kart LCD tachos that use a wire wrapped around one of the ignition leads and fit that under the engine cowl. They are a great tool for tuning , they can act as a double check for the dash tacho (both should read within 100rpm of each other) and almost all of them record engine hours for maintenance intervals - so no over/under maintaining excuses!

[@courtneylang7477]

Thanks Ron! You are really knowledgeable! I wired it up and tried a few settings. Turns out it's the 6 pulse setting for this after market tachometer. Now that I have it installed and functioning correctly, I can start my next project: **Determining which pitch prop I need for the load I typically carry.** I probably should have just bought one of those tiny tachs that wrap around the ignition lead like your suggestion. It would have been much faster and simpler.

[@arkdiver4824]

Hey Stu, if electronics are wired straight to one battery and you say to alternate charging batteries every week or so. Would electronics drain the battery if you were charging the other?

[@arkdiver4824]

By switching battery charging, are you physically removing battery lugs and installing on the battery that will be charging?

[@peteramberley9952]

Great vid stu .i dont know how salty it is where you are but would you recommend a grease (diachorlic grease) or something to protect the wires in the trrminals and the battery connections from corrosion in the salt air.many boats i have had i have suffered problems with the copper cables going black and losing continuity and i had to cut the ends off and strip the cables shorter to find clean wire. I didnt know weather you would recommend useing grease inside your taped or heatshrink joints even to stop them sweating ?

[@ronpowell2373]

I am a bit surprise he didn't solder the crimps/cables to stop the cable corrosion problem. But this looks like Stu hadn't got things quite lined up supplies wise before he made the video. Things like using red heat shrink on positive lead ends, using glue filled heat shrink to seal the ends of the cable from salt water, no battery terminal protective spray are all hints this was the more typical job most people would do rather than the normal ' best practice' mode Stu usually shows.

[@DangarMarine]

+Ron Powell Yes, I was a bit over it that night. Given there is only one crimped connection and that cable is about twice as long as it needs to be I think I'll shortened it and redo it properly. I must get back to doing the midweek "quick tip" videos. I'll do making battery leads properly as the first one. ;)

[@callumwearne7870]

Haha yeah mate what happened to the midweek quick tips? We are missing them ;)

[@DangarMarine]

What glue do you use Ron? I presume a resin epoxy would work nicely.

[@DangarMarine]

I'll do some more for your Callum. ;)

[@tonysou803]

With this set up can u safely charge them together? Where do u clamp the charger clamp?

[@unsaltedlife5998]

I always have 2 battery’s on my boat. However I found a 1300 amp emergency power pack to bring with me and you can even change your phone or MP3 player as well. That gave me a extra battery for my other boat, yeah you can never have to many boats.

[@richardc2803]

good video.. what bad thing happens if your engine is running and you move the switch to position ALL or 1 or 2?

[@DangarMarine]

Most of these switch are a "make before break" design so they aren't every off until you explicitly change to the off position.

[@richardc2803]

@@DangarMarine So, I can safely have the engine running and switch between battery 1, 2 and ALL ?

[@kmattar]

If it’s a 12 volt boat, why does one need to switch between the batteries independently rather than connect them in parallel? A simple on/off switch is cheaper too. What am I missing?

[@crispernator]

gday mate excellent video i never realized it was so easy to put dual batteries in may have done it otherwise me and electrickery dont mix , at least your batteries are in boxes some i have seen are shockers no tie down no box disaster waiting to happen . At one point you connected the positive and negative to the positive terminal ill have to watch again maybe i got it wrong anyway great video on how tooo.

[@DangarMarine]

Yes, having dual batteries isn't too hard at all. Having them strapped down or otherwise restrained is a must though in boats!

[@Cornuts1000]

Can you tell me how to wire up one of those switches with only one battery. I have about 4 different wires for different things wired to the positive and negative terminals of my battery. Do I just buy a short 6 gauge positive jumper wire and connect to the switch? Or do I have to put more wires on the switch? should there be any other wires wired to the switch. I bought my switch a year ago but no idea how to wire it .

[@awesome69691]

are u based on the hawksberry river brooklyn

[@johnmoran7324]

HI Stu johno from Bangor here. Just adding second battery and dual selector to my own boat and have found your video a great help. One question if you could help. Are your batteries Starter type or Deep cell or are they a mix? Or are they the same? Suppose that's more than one question. But what do you think 's best . Regards Johno

[@DangarMarine]

Both my batteries at starter batteries. They are find for running the small lights etc on a boat.

[@MrJockoDundee]

Connect the positives of any house battery connections to the "Charge" or "Engine" terminal of the switch in order to turn OFF ALL systems when the switch is in the OFF position

[@erikstyles8756]

Do you need a Inline fuse from battery to switch or just from battery to fuse block

[@ninja636king]

Mine kit came with a 2nd box. I did not see you use. I just got it installed. But with switch in OFF position. I still have a red light on 2nd box. Stating it is charging battery 2. Why is this , with switch off. Will it drain my 1st battery? Did the shop hook it up wrong?

[@djhinormas959]

i did my dual battery setup 2 weeks ago lol but stilled watched the vid anyways always good for a chuckle :) good stuff stu

[@DangarMarine]

Thanks mate! ;)

[@ramonangel3]

Would you place batteries under the boat floor.. In the bilge area where boat seems to have space for bigger batteries?

[@DangarMarine]

If you put them in battery boxes and strap them down they should be fine.

[@eddyz166]

If you select battery one and two will the outboard charge both at the same time ?

[@StewartGartland]

"if you squint you can imagine it's heatshrink!" lol

[@imasoccerholic]

He's funny. I also lolled when he said "and wishing I was a truck driver." Haha.

[@chancewalters9493]

Stewart.

[@TonyAnschutz]

just me swearing a bit, contorting and wishing I was a truck driver! Ha

[@jacobtaylor4258]

@@TonyAnschutz i am a trucker, if he thinks that's hard work, come give it a try, i dare ya

[@ngneer999]

Now you need two bilge pumps; one from each battery. You could also do the same thing with one bilge pump and two diodes but you'd probably need some heat shrink tubing for that complicated of a device.

[@DangarMarine]

A couple of bilge pumps would be good extra peace of mind. The sake of $200 it could save me a lot of time and money down the track, particularly with an old hull than doesn't have a lot of freeboard in storms with large wave height. They generally go down because rain makes them sit low enough in the water for waves to start coming over the transom. It all happens very fast after that.

[@ngneer999]

I'm just thinking that I'd hate to see that thing sink if the bilge pump battery goes flat and the other battery is still full

[@pimpshack81]

I’m really late to this video.. but how would I wire a switch where I have 2 12v batteries wired in parallel for trolling motor and other accessories and one 12v battery for starting ?

[@Celestian_Trader]

Subscribed. Love the videos man! Keep them coming! Thank you for your expertise.

[@DangarMarine]

Thanks Dustin, glad you've been enjoying the vids. :)

[@mmmarti9775]

What size wire are you using from battery to switch?

[@11bayrat]

Hey sty thanks for sharing!my 4.5 outboard motor will only run if the choke is pulled out 1/2 way!or it will not stay running.Is this a carb problem?it has new gas and a good oil mixture.

[@DangarMarine]

Hey Bruce. Certainly sounds like it. Pulling choke it making it run richer so it sounds like the idle jets might be blocked and the choke is compensating for that.

[@11bayrat]

Dangar Marine thanks for the help on this!now I know what to pay attention too when I take it apart.

[@sean2743]

so is it better to bridge 2 batteries together ,or run 2 solo batteries .... or does it really make a difference.. atm i am running fish finder and lights off one and motor and power trim off the other.. would it make sense to bridge them? also have a 2 bank on board charger would this effect that at all?

[@DangarMarine]

I had them separate so that one could go flat if you left lights on etc and then the other could still be used to start the engine.

[@Mr51Caveman]

This may sound like a stupid question but I've heard the only stupid question is the one that's not asked. I bought a 94 Hurricane Deckboat. 24 ft with a Yamaha 150 2 stroke. It has 2 batteries already installed and a buttload of wires connected. How do I determine which wires go from which battery to where? When I turn the Battery switch to say #1 I get nothing. When I turn to #2 I get SOME things but I have to turn it to "Both" to get the engine to start! Has me confused. And the batteries and wiring is stuffed in this little hole so it's very hard to see where the wires are going. And oh yeah...it has a Battery Management system which is throwing another wrinkle into things. It looks to me that the previous owner/s jury rigged some things and I can't find a schematic on the boat or engine anywhere. The Battery switch has only the 2 "hots" going into it and all the other wires are on the batteries. So some things are always "On". I'm afraid I will have to disconnect pretty much everything and "chase" the wires to figure out which ones go where!

[@keithfurman6245]

is a marine battery bad to use all the time on the boat due to it constantly calling for charge vs a common battery witch when charged will not over work the alternator? Thanks in advance Keith

[@DangarMarine]

I've never had any problem with these marine batteries for both cranking and running lights etc. They seem to be a good general purpose design. For a larger boat you might want a deep cycle house battery and a separate cranking battery but on a little boat I find this type perfect.

[@Dhi-fe5eu]

Where would you set the dial if you were going to charge your batteries with an onboard charger. 1, 2, both, or off.

[@DangarMarine]

I would set them to off if they were being charged from shore power.

[@JohnVH-diy]

After crimping the lug in the vise I take a punch and make a dimple in the lug which keeps the wire from pulling out.

[@nitrolx]

Nice work mate! What I'm sort of leaning towards these days is a kind of combination of all the options you mentioned. A lot of boats are wired similarly to your example there; a 'house' supply and the outboard/engine start/charge cable. I split them and use 2 battery switches. Engine to the common output on switch one, house supply to the common output on switch 2. DC-DC charger (or simple VSR) between the 2 batteries. In normal operation, 'engine' switch is Batt 1, House is Batt 2. With engine running, it's charging the start battery and through the DC-DC charger (or VSR) it's charging both. As soon as you stop, you've isolated the start battery and running the house off the second battery. Even if batt 2 goes flat, as soon as you hit the key, you're starting off batt 1 and you'll start charging your house batt again. It also adds the flexibility of turning off just the engine supply, or the house, or both. Also swapping over and starting off the house battery. Or charging the house directly from the engine, or charging both, or starting off both. Very flexible. It's a slightly more complex solution and most likely overkill on a boat like the green machine, but once you get up into cabin boats with more complex house loads it works really well.

[@ronpowell2373]

Have a look at a voltage sensitive switch for auto charge/disconnect if that is what you are after.

[@DangarMarine]

I like the idea of charging both batteries as well as having the isolation be automatic. You are dead right though that as you step up to live aboard boats power management becomes much more important. I was once staying on my friends boat for a few weeks in Greece and much of our conversation centred around resource management. In port you have plenty of power and water, but sewage tank capacity was critical due to no pump outs, but at sea the opposite was true.

[@str8wick3d]

so ground doesnt mater? for example neg cable from starter goes to bat 1 but we have pos from bat 2..

[@DangarMarine]

Yep, that's right. The negatives between the batteries are bridged and then you only select which positive you are drawing from.

[@str8wick3d]

reason i ask.. so in a setup with lets say battery 1 and it powers the lights and we have battery 2 that starts the motor separate circuit. could i ground the lights to the starter battery and they still work?

[@PerrynBecky]

Hey Stu, if I was to wire my bilge pump to a switch in the front of my boat, (the lead will be 10 ft), would I be able to use the aluminum boat itself as the ground source? (This boat is strictly in fresh water), or would that cause an electrolysis problems.

[@DangarMarine]

Personally I would never use the hull as ground. I've seen it done even in salt water but I wouldn't take a the risk.

[@bos3odalmannai451]

How can i change main piston seal in yamaha 85 outboard if you can mack vedio about it

[@LongStraightLines]

Coopers beer.. good choice!

[@DangarMarine]

The best. :)

[@LongStraightLines]

@@DangarMarine brilliant vid on this subject too mate!