how do wire bow and stern lights with switch?

[coolguy147]

well so far my lights are working perfectly fine with my 1958 35hp johnson. turns out that the hot wire that gives power to the switch is running from the key switch to the light switch. i do not believe this is the right way?

anyways, my story is that i will be taking the 35hp motor off and putting a 1961 mercury 500. totally different ignition systems. the keyswitch is ran from the box while the 35hp is ran from the dash mounted keyswitch.

my solution is to run the one hot wire to the positivie end of the battery. now i am sure that this will work but i have one question.

is it ok to ground the light both bow and stern light to an alumium boat? or should i run both wires to the negative end of the batter?

heard somewith with electrolysis or something like that. thanks in advance!

 

[coolguy147]

Re: how do wire bow and stern lights with switch?

oh yeah i forgot to add i am using 16 guage wires. i will be putting a fuse between the batter and hotwire.

what type is fuse should i use? 16 guage suffucient wiring for this purpose?

what about future plans on a bilge pump?

 

[triumphrick]

Re: how do wire bow and stern lights with switch?

You are on the right track...but don't rely upon the boat as a ground. That works fine for cars, but you are right when you mention electrolysis. You can run the common of the lights together, and to the negative battery post or to a negative buss bar if you have one. Your switch is providing +12v to the lights. Some switches have that lead connected to the center post and up turns on one light and down turns on the other. Make sure you have that circuit fused...close to the battery if possible. I would guess 10 amps would protect you. Can't see them pulling more than that. If you use an inline, you can pick your choice of fuses...good luck! And if you bring it to the get together we will all be there to help!

 

[coolguy147]

Re: how do wire bow and stern lights with switch?

i am sure the switch is 12 volts. it only has one connector for the lighs so one connector for both lights. works just fine. the setup i have now is the hot wire goes to the key switch. then ground wires from both switches ground to the boat. it works just fine.

i really do not want to wire both ground wires to the batter because it is quite a hassle.

if i do not though, it will cause electroysis? what exactly electroysis? is it the build up of corrosion?

 

[Triton II]

Re: how do wire bow and stern lights with switch?

Hi Coolguy,

As Triumphrick says, do not use the hull of the boat as a ground. If you have one light switch for both bow ansd stern lights I suggest you run wires as follows:

Positive battery terminal to stern light positive with a 10 amp inline fuse - stern light negative to switch negative - switch positive to bow light positive - bow light negative to battery negative. This loop type circuit isolates any "wigglyamps" from the hull avoiding potential electrolysis. It also isolates the entire circuit in case of a short, but is so simple that fault finding is a piece of cake.

For future bilge pump wiring I suggest a similar separate switched and fused loop type circuit. If you're considering adding other lights or electrical devices then maybe an early investment in a switch block would be worth a look? Good luck...

TII

 

[coolguy147]

Re: how do wire bow and stern lights with switch?

ok i will run both grounds to the battery and hot wire to the battery.

would a regular hardware store sell 10amp fuses ? inline.

 

[Silvertip]

Re: how do wire bow and stern lights with switch?

You do realize that a simple on off switch is not the proper setup. When you are anchored (as in not moving) only the stern light should be on. When moving (even drifting, both must be on. There are basically two ways to do this depending on the switch you have. Here are both ways:

Using a six terminal ON-OFF-ON switch you don't need a diode.

Usng a three terminal ON-OFF-ON switch you need a diode (cheap at Radio Shack).

 

[coolguy147]

Re: how do wire bow and stern lights with switch?

does radio shack sell a 6 terminal switch? where does the middle and bottom left terminals connect too?


my main question though that it is the right thing to ground the negative wires to the battery and use a 10amp fuse while running the one hot wire to the battery?

 

[coolguy147]

Re: how do wire bow and stern lights with switch?

http://www.radioshack.com/product/index.jsp?productId=2062537
found the 6 terminal 3 way switch.

http://www.radioshack.com/product/index.jsp?productId=2102786
fuse holder.

http://www.radioshack.com/product/index.jsp?productId=2103757
fuse.

how does that look?

 

[Mark_VTfisherman]

Re: how do wire bow and stern lights with switch?

...my main question though that it is the right thing to ground the negative wires to the battery and use a 10amp fuse while running the one hot wire to the battery?

Looks like you found the 6-term switch. It's not actually a "three way switch" BTW; actually called a DPDT (double pole double throw) but *does* have three positions.

Your other question as far as where the "left" wires go to is answered in Silvertips diagram. The middle two terminals are bridged, and bottom "side" runs the stern light leaving the lower left terminal unused; the other side (top) connects as shown on the diagram to the bow(left) and stern light (right).

Yes, the negatives should go directly to the battery. There should be no "ground" on the light switch.

That answers your specific questions without adding anything extra to it. Hope it helps.

 

[ENSIGN]

Re: how do wire bow and stern lights with switch?

Go with the DPDT switch setup the diode is just something else to go bad.

 

[Silvertip]

Re: how do wire bow and stern lights with switch?

Is the boat you are wiring the same one in the picture in your posts? If so, there should be a ground point at the console as well as a source of 12 volts. No need to run all the way back to the battery. 12 volts and ground are wherevery you find them. There is nothing wrong with using the diode. If it opens you will never know it. If it shorts internally you will know that since both lights will be on in either switch position.

 

[coolguy147]

Re: how do wire bow and stern lights with switch?

ok let me repeat how my boat is wired. the bow light has 2 wires coming from it. one to the switch and one to a ground on the boat. the stern light has 2 wires. one going to the the switch and one grounding to the boat. the one hotwire that supplys the switch goes directly to a spot on the key switch.

my plan

take is instead of running the hot wire to the key but run it to the battery with a 10amp fuse in between.

is it ok to leave the ground where they are so i would not have the hassle of running both of them to the battery? i am not quite understanding what you guys are saying. sorry i just am not really experienced in electricity.

 

[coolguy147]

Re: how do wire bow and stern lights with switch?

the colors in the front and back right side of boat are the lights. black is negative and red is positive wires. teal is the switch. then retangle the is the battery in the back.

does my diagram look ok?