Relocating House Loads

[Theo Lewis]

Greetings A4 friends,

My A4 does now start reliably, purrs like champion for extended crossings and gets my crew (family) home safely after the knowledge provided by the post archives, forum contributors when the answers weren’t apparent, parts and advice from MMI, several bloody knuckles and of course… many magic words over the last few years. Best part is the boat is no longer a massive fire hazard. Thank you.

Since I am running reliably I am turning to the spaghetti bowls that are my electrical box, switch/fuse panel, instrument and ignition panel and finally engine compartment. Everything ON the engine now belongs there; replacing poor quality wiring, connectors, terminals and bad patch jobs will be ongoing. Rerouting and securing will also be entertaining. I do have a good assortment of Don Casey and Nigel Calder reference works to ponder.

Looking for some discussion on pros and cons to relocating the house loads from their original power source, which I learned from a schematic (attached) from this forum, is the outgoing side of the ammeter. I was relieved recently after an afternoon of boat yoga, wiring a new chartplotter, to find that my A4 appears to be wired as originally designed per the wiring diagram (attached). Albeit with a couple hundred patches, every kind of wire imaginable from Romex to audio speaker wire (how expensive is respectable tinned copper really!) All the gear, major parts of the boat are top notch but the wiring all appears to have come from garage scraps and the corner auto parts store.

My plan has been to preserve and isolate the engine wiring per the original schematic with the exception of removing the house loads. Instead follow what appears to be conventional wisdom and run a 30 amp cube fuse off one of the two House/Start batteries to feed the house loads and their spiderweb of systems and wiring. Also considering just running the 30A fuse off the battery selector switch.

Thoughts or advice welcome.