I have an old 1974 16ft alumacraft boat that I would like to wire for lights,bilge pump,accessory plug. The boat has a 4 inch splash well that that I can mount a fuse block under. My question is do I need more weather protection and is there a commercial cover that would work? What gauge wire should I use for the running lights, bilge pump. The plan is to fix the old boat up for family members to use and not worry about any small dings. Thanks for any help .

Take a look at the supply wires for those compnents. None of them should be more that 16 or 14 guage (check the amperage draw for each component). Given that, and that they probably won't be running at the same time, 14 will probably be O.K.

I don't know if this is an open boat, or a boat with gunnels.
In any event, to hold the wiring and to protect it, use pvc tubing.
You can pick up a piece of 1/2 inch or 3/4 inch thin wall tubing from a hardware or big box store for about $3.

Mount this pipe to the side of the boat if it is an open boat by using nylong straps and pop rivits. If you have gunnels, you can simply mount it under the gunnels.

Pull your wiring through this pvc pipe, and you never have to worry about drooping wiring or breaks.

Take care
REW


p.s.
If your fuse block is on the underside of a surface, with some kind of a protection in front, that is all you need for the fuse block.

REW has good suggestion for running wires etc. As for fuse block, it should be okay under spashwell if you dont get much water over transom. I guess your looking at the auto style fuse blocks, much prefered over glass fuses. Also suggest you coat the terminals in an electrical silicon or liquid tape to keep moisture and corrosion off the terminals.

You could also use outdoor extention cord for wiring, flexible and tough.