Battery and wiring

Discussion in 'Boat Yard Basics' started by firecat1981, Oct 8, 2009.

  1. firecat1981

    firecat1981 BBA Counselor

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    ok I just picked up a motor and now I think I need to change some plans do to the fact that it is electric start with an alternator. first let me ask about the wiring.

    I have from the battery 8ga wire to this battery switch
    [​IMG]

    to this fuse panel
    [​IMG]

    and then from the negative bus bar on the panel back to the battery with 8ga wire.

    So will I be able to hook the positive side to the battery switch and the negative side to the bus bar? and is the 8ga wire heavy enough?
    or will I need to get thicker wire to the battery switch, hook the positive motor wire to it, and then run the negative motor wire all the way back to the battery?
    Next I need to know about batteries. I was going to get a group 27 deep cycle but now with the starter will I need to get the dual purpose one? Will it power my livewell and trolling motor the same? I can't have 2 batteries so I need to know which type will do the job the best and what the real differences are?
    heres some motor porn.
    [​IMG]
     
  2. mark_gardner

    mark_gardner I Love microskiff.com!

    i would definitely run the motor off 4 ga. wire. what was the other question? oh yeah go with the dual purpose batt. :cool:
     

  3. Brett

    Brett > PRO STAFF <

    Here's a wiring gauge chart for general reference.
    I have a copy taped to the lid inside of my electrical toolbox.
    Makes it easy to find when I need it.
     
  4. Frank_Sebastian

    Frank_Sebastian Well-Known Member

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    I bought some welding cable last year for a really good price, but I can't remember or find where I bought it. I tried several searches without any luck, but it was almost half the price of marine wire?

    Frank_S
     
  5. Frank_Sebastian

    Frank_Sebastian Well-Known Member

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    It was a site similar to this http://www.cableyard.com/catalog/product_info.php?products_id=30&osCsid=e8085f2bba7024dbbdd36fe2a853a3f3

    Still that isn't too bad of a price. It is available in red as well.

    Frank_S
     
  6. firecat1981

    firecat1981 BBA Counselor

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    how many amps does the starter draw? I know it has either a 10 or 12 amp alternator so the 8 ga I already bought would work just fine since according to that chart it is rated for 80amps, but I would like to be safe. An electrician I work with thought the 8 would be just fine as well and the 4 would be over kill, but didn't know about the actual starter. Keep in mind my battery is in the front of the boat so it has to be run atleast 11-12ft. what to do? :-/
     
  7. Brett

    Brett > PRO STAFF <

    Starters spike the amperage pretty high.
    Check with Yamaha dealer regarding the starter load.
    If the battery required is 350 CCA for your engine
    that ought to give you a pretty good idea of the amp draw.
     
  8. firecat1981

    firecat1981 BBA Counselor

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    called yamaha dealer today, the tech said 4 should be fine, I hope it wll fit through my pipe chase
     
  9. tguasjr

    tguasjr Fish Finaddict

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    I have 1 24 series deep cycle battery that serves as my starting/trolling motor batt. I have 8 gauge cable running from the rear of the boat to the trolling motor about 12 feet away. I also run the same gauge wire to my motor from the batt. I have yet to kill my batt after using the trolling motor for 4 hours straight and it starts my motor up instantly. IMHO 4 gauge is overkill.
     
  10. firecat1981

    firecat1981 BBA Counselor

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    it might be overkill, but if the yamaha tech says use 4ga, Imma gonna use it. I picked some up this morning and it's not as thick as I thought so it should still fit nicely in my pipe chase. the only think is they did not have red, only black in stock so I'll have to mark one of the lines.

    My plan now is run 4ga to the battery switch, then to connect the positive side of the motor to the battery switch, then splice the 4ga into the negative side and run that all the way back to the battery. sound good?
    My other electronics will be 8ga (gotta use it somewhere) to the fuse panel, then 8a from the negative bus bar back to the battery. I hope this is the last time I need to revise this all.
     
  11. tguasjr

    tguasjr Fish Finaddict

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    Yep!, sounds good. Instead of splicing the wiring to the motor, why don't you use a distribution stud to the negative? It's a stud mounted to a plastic piece that you bolt down to the boat. You run your negative wire to it and then hook up all your negative connections to the stud. With this one you can use it for both your positive and your ground.
    http://www.jamestowndistributors.com/userportal/show_product.do?pid=1202&familyName=Blue+Sea+Systems+PowerPost+High+Amperage+Cable+Connectors
    With this one you can hook your battery ground on one side and the motor on the other accessories in the middle.
    http://www.jamestowndistributors.com/userportal/show_product.do?pid=8978&familyName=Electrical+Bus+Bar+10+x+8-32+Stud+150A
     
  12. firecat1981

    firecat1981 BBA Counselor

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    if you look at the fuse panel picture I posted you can see it already came with a bus bar for the positive and negative sides, however it has a smaller stud on it like a number 10 so i feel more comfortable just running it all the way seperately.
     
  13. The_Skiff_Shop

    The_Skiff_Shop Well-Known Member

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    4ga from the battery to the studs "tico"suggested.

    Connect motor directly to the studs - it should already have the connectors.

    Run 8 or 10ga to your buss bars.  It wouldn't hurt to inline fuse the positive side.

    How are you gong to protect your fuse/buss bar block?
     
  14. firecat1981

    firecat1981 BBA Counselor

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    I am running the 4ga to the battery cut off so if I got a stud I would only need one. as far as protecting the bus bar goes why would I need a fuse to protect a fuse panel?

    I am running out of time, where can I get one of these studs locally? (pepboys, discount auto parts?) I am starting the wiring tomorrow and don't have time to wait for internet orders.
     
  15. Brett

    Brett > PRO STAFF <

    Nothing but an insulated 1/4 inch bolt.
    You could assemble one from a scrap chunk of starboard.
     
  16. The_Skiff_Shop

    The_Skiff_Shop Well-Known Member

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    You need to also connect the negative side of the motor.  Most people don't understand that the negative side is actually more important to get right.

    Since you don't state what you are running off your fuse block and assuming it's reserved for switches, I'm allowing for an automatic bilge pump, the only thing that gets wired direct.

    Like Brett stated, it's just and insulated bolt and you can make it.

    All the parts you need are a available from a local marine supply, you may just pay a little more.
     
  17. tguasjr

    tguasjr Fish Finaddict

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    I'm just making a suggestion. I run my battery in the rear of my boat. I have my motor on a quick disconnect marinco plug that is wired directly to the battery. My switch panel, is directly wired to my battery with 10 gauge marine cable. All my accessories are run with 16 gauge marine tinned and insulated wires.You could also run your fuel tank up front only having to run a simple fuel hose from the front to the rear. Just trying to help! :)
     
  18. firecat1981

    firecat1981 BBA Counselor

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    I understand this, thats why I was going to run the negative by itself back to the battery. and if I don't the negative side would not be bolted to the batery cut off, that would actually negate the cut off switch all together wouldn't it. the battery switch would do the same job as the post for the positive side which is why I don't see the need for it.

    it's a 6 fuse switch block, 4 will go to the switches for the livewell and lights, 1 to the bilge pump, and 1 to the depth finder/gps eventually, but all will be fused through the block, if I need to add anything else later on I'll just add an inline fuse for that.

    Ii need further clarification on this one. would just a 1/4" bolt covered in liquid tape work? if not how else do I insulate the bolt without directly bolting it to my boatside?

    Problem is there are no local marine supply shops here, closest one is west marine which is almost an hour away.

    Thanks for the help, I know this is a headache, especially since this is the 4th time I've revised my plans for the electrical system.
     
  19. firecat1981

    firecat1981 BBA Counselor

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    My battery will be in the front along with the gas tank(see my build blog for pics of the supports). so I can't do as your suggesting. I already have the wire for my accessories along with the fittings. I have pipe chases to keep the fuel and electrical completely isolated from each other. basically the negative setup for the motor is the last piece of the puzzle for me.
     
  20. The_Skiff_Shop

    The_Skiff_Shop Well-Known Member

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    Typically, the battery cut off is located near the battery/batteries.  Thought I read you were running a trolling motor :-/  If that's the case, you would need to another 4ga for the trolling. If not, you could do it that way.

    That will work, you just want to protect the fuse block from the elements and gear.  Uncovered, inside a hatch isn't really a good plan.