Post 43 Cruise Speed?

Great diagram...and lucky me!

I do. Tested it last year with my meter on diode setting and it is working. On more than one occasion a diver cleaning other boats got shocked getting back on the dock. Marina management company pretty much ignored it. I moved to a different marina this year so curious to see how the zinc wear compares. All new wiring since Sandy so hoping to see an improvement.

I gotta read up on this basic stuff this weekend...I don't know why but I have always had a mental block regarding all things electronic. Time to nail it down once and for all (wait, I think I said that before....)

I read "From my Boat" Like an emitter and giving up material (atoms & ions). A well bonded ship with zincs is first line of defense. The zinc will give up it's less noble material before bronze. A galvanic isolator will help a lot and cut that DCv lead to/from other boats.

I can also read "From my Boat" as the culprit boat.
There is a long list of things that can cause stray currents. Usually poor installation of BuBBa's window AC install or as honest as an inverter fault relay getting set incorrectly or use at the dock. Some old generator installations may have a problem. As an inverter, gen sets tie green and white wires together, usually to DCv negative on the block. Not a problem when the transfer switch is open or away from the dock. A problem if only the black & red wires are open at the transfer switch.
I heard stories of leaking wind generators and solar panels.
There are codes, some complicated, that help.
BuBBa don't need no s$%^^& instructions..
Bad battery chargers, poor wire condition Yada Yada.

The culprit boat could to be well bonded or he may be eating up some of his own equipment. Zincs may not help Bubba.
Now if Bubba had a galvanic isolator, it could help also by cutting that DCv line to/from other boats.

Don't forget mother nature. Just when you think it's all figured out, she throws some loose currents of her own from somewhere else (AKA unexplainable Stuff happens) and your parts still dissolve.

Last note. IMO, a galvanic isolator is a great tool in your ships defence and protection. NOT the only tool. Zincs take a bit more maintenance in and under the boat. I have & use both. My new thru hulls, oil coolers, heat exchangers and thingies in the water I feel are fairly safe.

Thanks RC. I've always been **** about my zincs, and I have a diver every month to put eyes on them while cleaning the bottom. I stay on top of the bonding too. I know there is a galvanic isolator on my GB, now I just have to make sure there is one on the Post.
Very useful info, thanks!

I have always been fastidious (yeah, that's it) about my zincs.

There is no galvanic isolator on the boat. Are there any favorites or, brands to avoid?

I like the Guest ones. I had an issue on a yacht where the zincs only lasted 6 weeks, everything was tested on the yacht itself and checked out fine but the marina was the issue or a boat around it, and installed the Guest and the zincs immediately started lasting 5-6 months.

I think Newmar would probably be good as well, but my preference is Guest. I'm not a fan of any Promariner products since I've seen a high failure rate on their chargers and such.

OK thanks CJ!

Marine Grounding Systems | West Marine

Interestingly, this article from Practical Sailor argues against bonding your submerged metal if your boat spends a lot of time in a marina with other boats. The boding helps to mitigate any stray current from my own boat, but at the same time makes my boat vulnerable to stray current issues on neighboring boats.

BTW a cursory internet search reveals this is a controversial issue. There are as many opinions regarding bonding as there are authors...

Well......I'll tell you a funny story. Roy Merritt swore against zincs on his own boat, a 46' Merritt and felt that zincs make barnacles grow faster and this and that. He always kept his boat docked at Merritt's. Well one day a boat came in and docked in the slip next to his boat at his marina and stayed for a while and nobody knew it had a grounding issue. Roy went to use his boat and the propellors had been totally eaten away by electrolysis in less than a month and what was mostly left was the hub......

Even if zincs did attract stray energy from a neighboring boat, they are less noble metal on the bottom of your boat and would wither away first.

Ouch! Well at least he's not overloading his motors

Roy Merritt aside, I think most people use zincs. There may be some minor controversy surrounding the use of zincs but I think they are generally accepted and regarded as necessary. Bonding on the other hand is much more controversial: to bond or not to bond, and is where the biggest debate rages I think

Anything that has sea water passing through it and is metal, should be bonded. I have never, ever seen a premature thru-hull or seacock failure because it was bonded correctly.

I have seen many instances where something was isolated by rubber hose on both sides and unbonded with very poor results. For example, A 48' Formula I do the maintanence on, has 4 sea strainers for the air conditioners (1 for each). The sea strainers were unbonded and that boat would eat the s/s baskets every 2 months.....if not sooner. I bonded them and they now at least 6 months if not 9 months. Everything is kept well on the boat, zincs etc.

Gotcha. It sounds like the real question is 'what hardware is really isolated.' The anti bond people believe that isolated hardware exists whereas the pro bond crowd contends that because seawater is a conductor there really is no such thing as an isolated thru hull fitting...it's all connected.

Anything sea water passes through is connected. I even was on a Maiora that had a short on the earth side. You could put the volt meter leads anywhere in the bilge water of the entire 80' boat and measure around 75 volts AC as well as getting the XXXX shocked out of you.

Well the post-survey negotiation is all wrapped up. We close next week! I wanna close today but have to wait. I'm stoked! Thanks for all the input through this process!

Next week we transition from theory to reality

Congrats, guarantee you will be happy with you new Post.

Hope you like your Post as much as I do! Enjoy!!