Adding Circuit breaker/Fuses

[Slacker411]

I want to know if I need to add a fuse or circuit breaker to my trim pump and ignition which are on my side mount controls. I also have lights and a fuel gauge which do not have any fuses or circuit breakers either. I bought the boat this way, but I would like to make it as safe as possible.

 

[NYBo]

Re: Adding Circuit breaker/Fuses

The trim pump, ignition switch, and fuel gauge are all protected by the main motor fuse, no need to add additional circuit protection. Lights should be on a fused circuit via the fuse block.

 

[Slacker411]

Re: Adding Circuit breaker/Fuses

I do not see a main motor fuse anywhere. There is nothing from the positive terminal on the battery to the motor wiring harness. I will attempt to attach a picture of a diagram of the way my wiring harness should be. Number 26 is supposedly a 20 amp fuse. I don't even have a complete wiring harness as shown in illustration 25. I can tell the prior owner did some ghetto re-rigging of the wiring harness.

<a href="http://s116.photobucket.com/user/dcsudnik03/media/wiring.png.html" target="_blank"><img src="http://i116.photobucket.com/albums/o25/dcsudnik03/wiring.png" border="0" alt=" photo wiring.png"/></a>

 

[Slacker411]

Re: Adding Circuit breaker/Fuses

 

[Slacker411]

Re: Adding Circuit breaker/Fuses

This is a 1978 Mercury V-1500 150hp outboard by the way in case anyone is interested in checking the diagrams available on **********

 

[Slacker411]

Re: Adding Circuit breaker/Fuses

Here is a pic that I think demonstrates the ghetto setup the prior owner did. Notice the cut wire harness in my hand with the 3 wires that don't go to anything. Disregard the purple to green wire with the orange twist cap on it. That is temporary as I just figured out the purple wire is my ignition accessory circuit and I was testing my new fuel gauge out to get it to come on with the turn of the key. That's working now. No fuses anywhere though.

 

[Fed]

Re: Adding Circuit breaker/Fuses

I found this old diagram which might help you.
If you follow the wiring through from the alternator and the battery there is no fuse at all.

The place to install one would be an inline fuse on the red wire in the external harness.

 

[Slacker411]

Re: Adding Circuit breaker/Fuses

I wish I knew more about electronics and using a multi-meter. I do have one, but how do I test to see what amperage fuse to use. The wiring diagram I posted above mentions a 20amp fuse but I am confused if that is what I need.