battery wiring questions

[jawz12]

i purchased an older GW which has dual Yamaha HPDI outboards, two start batteries, a house battery, 3 battery switches and a guest charger. The wiring seems a bit messy to me. Does anyone have a wiring diagram that would be well suited for this application?

there's really no such thing as a diagrahm for this...you've gott ask yourself what do you want to accomplish...what i mean is,you should have a seperated and dedicated system,menaing the batteries need to be seperated.one battery for each engine and a seperate battery for the 12v system...using the 3 position switches will not accomplish this...i can't post,nor will i post a suggestion of wiring,reason being,if someone misunderstands something,or doesn't understand exactly what they're reading,it could be trouble...
now,i'm not making this out to be brain surgerey,but it's not for the inexperienced...
the yamaha hpdi engines have stators,not alternators...

consult with a competent individual is my suggestion,but beware of what shop you choose...just because you go to a dealership doesn't mena it's done correctly...check out the pics i atached,this is a real high end boat i recently rigged up for a customer.it came from a big name dealership,sold by a big name "sales person",the wiring work was done at the dealership,and the pics show,the work was done incorrectly...the starboard engine had power at it with the port battery switch in the off postition-nice huh ??? i corrected that situation...
again,beware of what and where you go...

here's the pics...

[jawz12]

there's really no such thing as a diagrahm for this...you've gott ask yourself what do you want to accomplish...what i mean is,you should have a seperated and dedicated system,menaing the batteries need to be seperated.one battery for each engine and a seperate battery for the 12v system...using the 3 position switches will not accomplish this...i can't post,nor will i post a suggestion of wiring,reason being,if someone misunderstands something,or doesn't understand exactly what they're reading,it could be trouble...
now,i'm not making this out to be brain surgerey,but it's not for the inexperienced...
the yamaha hpdi engines have stators,not alternators...

consult with a competent individual is my suggestion,but beware of what shop you choose...just because you go to a dealership doesn't mena it's done correctly...check out the pics i atached,this is a real high end boat i recently rigged up for a customer.it came from a big name dealership,sold by a big name "sales person",the wiring work was done at the dealership,and the pics show,the work was done incorrectly...the starboard engine had power at it with the port battery switch in the off postition-nice huh ??? i corrected that situation...
again,beware of what and where you go...

here's the pics...

let me add a few things here...
these pics,this shows how the guys ran the system,there's absolutley no seperation,it's a giant mess,batteries are paralleled,meaning,you're drawing from multiple batteries,not just one-as was lead to believe by the "installers"...there's really no way to charge the 3rd battery independently either,that's not good...

i'll give you this much...this is how i do things,and i'm not trying to reinvent the wheel,i prefer a bullerproof set up versus the cheap crap the mfg installed...
you've got an older gw,right ???
the wire from the battery switch that feeds the main breaker on the inside transom area,port side,should be an orange wire...you wanna feed this wire from a seperate battery switch,this is the 12v system feed wire...now,if you're real smart,you're gonna do away with that set up...feeding the entire boat's 12v system from a single 10g wire is pretty bad...but,that's how grady did it and still does it,cheap,real cheap...i would use a seperate breaker system for the 12v system,those cheap junk glass fuse set ups gw used is and was terrible,i like blue seas breaker panels...i would set the entire 12v system on breakers,feeding switches,the way it should be...this is gonna take a little time but the results are well worth it.....
here's a pic of a grady i set up using this approach...

[Questsportfishing]

first start out by lableing / numbering your port starboard house battery wires 1 - 2 - 3- etc., ... next take a look at the BEP switches they don't take up any room! they do what they are supposed to do and come complete! KISS <~~ still keep it simple stupid..lol never liked being called stupid though! use a 50 amp service breaker for house system and pumps and a 50 amp service breaker for your bilge systems. print laminate, draw whatever your system is under a hatch or put it in a book... but first look at bep switches even if it is just 1 engine and a house system they even have a paralele built in in case you need it and I don't think they have any ever come back bad.

[jjudge1]

Thanks JAWZ and everyone else. This info is very very helpful. I ended up stripping all of the wiring from the countless cable ties just to see what the hell was going on. I have both batteries isolated, which for me was concern #1. I think i will look at taking JAWZ advice on the 12V system. I have quickly realized that i have taken on way too many projects this year....its mid June and my boat is still on blocks!

Once again...thanks for all of your help.