Zincs and Portable Generator Honda 2000

[bayliner 285]

I use a Honda 2000 for my shore power. The dock we are at has no power on it. On my boat the reverse polarity light comes on when plugged into the Honda because it sends 60 volts on the Black wire and 60 volt on the white wire to make my 110 voltage. On the boat i have a Zinc Saver II on the shore power coming in and I checked it's statis and it is working correcttly. The problem I am having is that i put new Magnesium zincs on the lower unit and trim tabs last year and they are better than half gone already. They are pitting not shinny so from what I have read that mean it is a galvanic problem. I have not completly checked the bonding system yet but so far it is intact. I am looking for some ideas.

[Andina Marie]

Since you don't use shore power, do you have any other shore connections like cable TV, data cable etc.?

If there are no shore power connections the electrolysis is being created locally on your boat. Are you in fresh water? Magnesium is a high voltage zinc for use in fresh water. In salt water you should use normal zinc zincs. Magnesium anodes in salt water are just self destructing "over protecting" the boat.

Make sure all the underwater items are connected to the same place, typically the 12 volt negative. Check that the exposed underwater metal on each item is connected to the negative and if it is not, then bond them together with a coppoer wire. The wire carries nearly zero current so it only needs to be heavy enough to survive in the marine environment.

Once you get all underwater metal connected together any zinc loss is due to different metals in the water and you will have to live with it.

The Hoda 2000 and its strange grounding "should" have nothing to do with your electrolysis problem.

[bayliner 285]

Andina

Yes i am in fresh water and no there are no other connections for the boat. I will check the system out. Thanks

[fstbttms]

FYI-

"Electrolysis" is the separation of hydrogen and oxygen from water by means of passing an electrical current through it. It has nothing whatsoever to do with metal corrosion on boats. However, the term is frequently and erroneously used as a catch-all to describe any corrosion of underwater metal parts on boats.

"Electrolytic corrosion" is what happens when electrical current (from any source) attacks and corrodes underwater metals.

"Galvanic corrosion" occurs when two dissimilar metals are in contact with each other while immersed in an electrolyte, such as seawater.

This has been your "Please Learn and Use the Correct Terms When Discussing Boats" lecture for the day.

[bayliner 285]

Dear fstbttms

I am not having any other metals eating away on my boat but the zincs. According to different zinc web sights i went to the pitting of the zincs is from galvonic corrosion is what they say.

[ben373]

Hi,
I think part of the problem is that the Honda has no real earth. In Australia we us a MEM system - Mains Earth Neutral and I think you guys do as well. That is the earth and neutral are connected. The Honda out of the box does not have this so you need to bind the 2. An earth leakage type circuit breaker will not work if there is no MEM so this could be a way to test.

[mcon12000]

You need to make a neutral to ground bonding plug. It’s easy just go to any hardware store and pick up a bare Edison plug. Connect a small jumper between neutral and ground, close up the plug and plug it into the unused outlet on the generator. While you’re at it grab a grounding rod and clamp from the same store and drive it into the ground nearby. Now run a wire from this rod that you can attach to the grounding terminal on the generator. It’s usually a wing nut so it’s easy to detach for storage.

Now your power it N/G bonded at the source as it should be and your reverse polarity light will no longer be on.

[mcon12000]

You’re zincs being partially consumed after a year doesn’t set off an alarm for me. Please keep in mind galvanic corrosion is a complicated topic and the guys who do it professionally are the only ones I would trust. So take everything you read on any forum and check it three times or call a pro it doesn’t cost as much as you think and it’s cheaper than ignoring it.

In the interim I would carefully check that your helm steering or any other area that has 12v DC service does not have any chafed wiring. For example it’s not uncommon for electronics to be installed in a Edson pedestal and over the years a 12v wire chafes. Now you have a path to ground via your rudder stock and or a complete circuit via the prop shaft. This situation can destroy a stainless steel rudder stock very quickly and most do not have a zinc or bond.

A pro can sort all of this in an afternoon and you can go back to enjoying the boat.

[sailorboy1]

Originally Posted by mcon12000

You need to make a neutral to ground bonding plug. It’s easy just go to any hardware store and pick up a bare Edison plug. Connect a small jumper between neutral and ground, close up the plug and plug it into the unused outlet on the generator. While you’re at it grab a grounding rod and clamp from the same store and drive it into the ground nearby. Now run a wire from this rod that you can attach to the grounding terminal on the generator. It’s usually a wing nut so it’s easy to detach for storage.

Now your power it N/G bonded at the source as it should be and your reverse polarity light will no longer be on.

this!! except I would not bother with the earth rod probably if were me

[mcon12000]

Originally Posted by mcon12000

You’re zincs being partially consumed after a year doesn’t set off an alarm for me. Please keep in mind galvanic corrosion is a complicated topic and the guys who do it professionally are the only ones I would trust. So take everything you read on any forum and check it three times or call a pro it doesn’t cost as much as you think and it’s cheaper than ignoring it.

In the interim I would carefully check that your helm steering or any other area that has 12v DC service does not have any chafed wiring. For example it’s not uncommon for electronics to be installed in a Edson pedestal and over the years a 12v wire chafes. Now you have a path to ground via your rudder stock and or a complete circuit via the prop shaft. This situation can destroy a stainless steel rudder stock very quickly and most do not have a zinc or bond.

A pro can sort all of this in an afternoon and you can go back to enjoying the boat.

Sorry my spellcheck put You’re instead of Your. Lol

[Statistical]

Originally Posted by bayliner 285

I use a Honda 2000 for my shore power. The dock we are at has no power on it. On my boat the reverse polarity light comes on when plugged into the Honda because it sends 60 volts on the Black wire and 60 volt on the white wire to make my 110 voltage.

Sorry the electrical engineer in me cringed. No your Honda is producing 120V AC at 60 Hz. There is no 60 and 60V (or pos and neg). There is a hot and a neutral (or in case of 120V/240V split phase two hots and a neutral). The reverse polarity light is on either because your neutral and hot are reversed or because that light is also being used to show a lack of ground (or both).

You can measure stray current pretty easily.
https://www.powerandmotoryacht.com/u...through%2Dhull.

Most people don't do it but it can give you an idea on how bad the situation is and can be used to identify the source(s). Suspect areas would be frayed insultation and/or connectors which have a wet path to the bilge or any other conductive surface. Both would allow DC current to flow from circuits powering equipment to the thruhulls or propshaft to the water.

If you do measure stray current you can try turning off components to see if the stray current goes down. If you get a big drop the component you turned off is the suspect one. Maybe not the component itself but the wiring to the component. If nothing switchable shows a drop in stray current when off it could be the always-on components and if you feel like the effort remove them one by one from the busbar to try and identify the source.

The alternative is just accept the level of stray current you have and change the zincs as needed. The zincs half degraded in half a year isn't great but you may find it easier to just change them more frequently. Me on the other hand it would bother me but I am a bit weird when it comes to electrical stuff.