Same boat, same marina for 5 years-slightly different slip this year.
Boat stays in water 8 months out of the year (Boston harbor). always
have mechanic change zincs when winterizing (he says he did so this
year). discovered the prop had been destroyed by electrolysis as well
as damage to engine trims. never seen anything like this before
pulled boat our and had mechanic put new zincs on. Cost for haul,
wash, new zincs, labor and put back in water-$500 plus the cost of
replacing the prop. mechanic and I decided not to wait on engine trims
can anyone tell me more about what to do about the electrolysis? does
anyone think that this is something that could be covered by
insurance. have never made a claim on any of my boats over the year so
have no clue
thanks

On Oct 11, 7:33 am, "Roger Long" wrote:
Sounds like you moved in next to somebody who has an electrical problem on
their boat. Marinas are scary places. Those zinc fish on a wire clipped to
the bonding system of your boat or the motor if you have an outboard are
absolutely essential. Not only do they provide additional protection, you
can tell that there is a problem if they disappear rapidly.

If the boat is back in the water and other boats haven't been hauled yet,
you might get an marine electrician to come out and take a look. First buy
the zinc fish and a digital multimeter. Put the fish in the water with the
meter hooked in between. Record the voltage. Then turn off the breakers
one by one on nearby connected shorepower outlets and see if turning off one
produces a drop in voltage. If so, that's probably the culprit. His props
are probably disappearing as well so he might appreciate knowing.

--
Roger Long

as soon as I saw the damage, I got one of those zinc fish while
waiting for a week to get the boat hauled. I wonder if you can be more
specific. Can I attach the clip to the negative on my battery? some
have said yes and others no. I have an 25 ft four winns IO. With the
fish hanging off the side of the boat, where do I put the two leads
from the digital multimeter? how far from each other ?
thanks Roger as always for your help

On Oct 11, 8:13 am, richard wrote:
On Oct 11, 7:33 am, "Roger Long" wrote:





Sounds like you moved in next to somebody who has an electrical problem on
their boat. Marinas are scary places. Those zinc fish on a wire clipped to
the bonding system of your boat or the motor if you have an outboard are
absolutely essential. Not only do they provide additional protection, you
can tell that there is a problem if they disappear rapidly.

If the boat is back in the water and other boats haven't been hauled yet,
you might get an marine electrician to come out and take a look. First buy
the zinc fish and a digital multimeter. Put the fish in the water with the
meter hooked in between. Record the voltage. Then turn off the breakers
one by one on nearby connected shorepower outlets and see if turning off one
produces a drop in voltage. If so, that's probably the culprit. His props
are probably disappearing as well so he might appreciate knowing.

--
Roger Long

as soon as I saw the damage, I got one of those zinc fish while
waiting for a week to get the boat hauled. I wonder if you can be more
specific. Can I attach the clip to the negative on my battery?

NO. NO..And NO!

If you have a grounding strip attach it to that. If not attach it
directly to the engine, or whatever you are losing metal on.

Best thing to check is do like Roger said and get a meter and measure
for stray AC and/or DC voltage. DC will do far more damage faster.

The best way to do it is to put one lead into the group terminal where
the boat plugs in at each slip, and one lead in the water, get a long
wire so you can walk out around the boats. If you have more than .4
volts DC and 1 volt AC then you have a problem. It sounds like either
you have a short to ground or one of your neighbors has one. If you
find high voltage around another close boat give him a bill for the
haulout and zincs and insist he pulls his boat until he gets the
problem fixed.

Joe


some
have said yes and others no. I have an 25 ft four winns IO. With the
fish hanging off the side of the boat, where do I put the two leads
from the digital multimeter? how far from each other ?
thanks Roger as always for your help- Hide quoted text -

- Show quoted text -

On Oct 11, 9:04 am, Joe wrote:
On Oct 11, 8:13 am, richard wrote:





On Oct 11, 7:33 am, "Roger Long" wrote:

Sounds like you moved in next to somebody who has an electrical problem on
their boat. Marinas are scary places. Those zinc fish on a wire clipped to
the bonding system of your boat or the motor if you have an outboard are
absolutely essential. Not only do they provide additional protection, you
can tell that there is a problem if they disappear rapidly.

If the boat is back in the water and other boats haven't been hauled yet,
you might get an marine electrician to come out and take a look. First buy
the zinc fish and a digital multimeter. Put the fish in the water with the
meter hooked in between. Record the voltage. Then turn off the breakers
one by one on nearby connected shorepower outlets and see if turning off one
produces a drop in voltage. If so, that's probably the culprit. His props
are probably disappearing as well so he might appreciate knowing.

--
Roger Long

as soon as I saw the damage, I got one of those zinc fish while
waiting for a week to get the boat hauled. I wonder if you can be more
specific. Can I attach the clip to the negative on my battery?

NO. NO..And NO!

If you have a grounding strip attach it to that. If not attach it
directly to the engine, or whatever you are losing metal on.

Best thing to check is do like Roger said and get a meter and measure
for stray AC and/or DC voltage. DC will do far more damage faster.

The best way to do it is to put one lead into the group

Opps TYPO put one terminal into the Ground terminal were the boat plus
in..not the "Group".

Joe

terminal where
the boat plugs in at each slip, and one lead in the water, get a long
wire so you can walk out around the boats. If you have more than .4
volts DC and 1 volt AC then you have a problem. It sounds like either
you have a short to ground or one of your neighbors has one. If you
find high voltage around another close boat give him a bill for the
haulout and zincs and insist he pulls his boat until he gets the
problem fixed.

Joe

some



have said yes and others no. I have an 25 ft four winns IO. With the
fish hanging off the side of the boat, where do I put the two leads
from the digital multimeter? how far from each other ?
thanks Roger as always for your help- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Subject

You have found a "hot" slip, usually a neighboring boat has an
electrical boat.

Option 1:

Move back if possible, if not some place else.

Option 2:

If you can't move, if you have shore power connected, disconnect it.

IOW, do as much as possible to electrically isolate yourself from your
environment as possible.

Temporialy, you can add some zincs, but you need to address this issue
with the marina, and quickly.

You are dealing with ground currents and cathodic protection, a place
where the faint of heart should not go.

Trying to be a ground current sleuth is difficult at best. I would not
waste my time, since it is only going to cost more money and may not
be successful.

Good luck.

Lew

On Oct 11, 11:26 am, "Lew Hodgett" wrote:
Subject

Trying to be a ground current sleuth is difficult at best. I would not
waste my time, since it is only going to cost more money and may not
be successful.


Good lord.. It's easy. All you have to do is map the marina with a
good volt meter.

If you have a hot spot near you.. you know who's to blame. All you
need is a meter and a long piece of wire. Put one lead into the ground
terminal of the plug, and one in the water and read the meter. Set up
a grid pattern and map the voltage in the area...simple. And it's very
easy to find out who's causing problems.

If this sounds complicted print this post.... bring it to a marine
electriction ...and pay him a couple hundred bucks to do it for you,
he will enjoy a nice day on the docks.

I had a boat next to me once that had a DC short to ground and he had
no clue. I showed him on the meter the voltage next to his boat and
down the dock. We turned off his power and Wa-La the voltage
disappeared. Not only did he waste his zinc's and part of mine, he
sucked to many electrons from all his bronze hull fittings and and
shaft tube that they turned that brittle shade of pink. He had a short
where a screw holding down the stanchions pierced a wire, and a short
to his running lights wiring on the lifelines contected to the
stancions.

Joe





Good luck.

Lew

"Joe" wrote:

Good lord.. It's easy. All you have to do is map the marina with a
good volt meter.

Spoken by someone with the perspective of experience and prior
knowledge.

Different ball game.

May response was aimed more at "the unwashed masses"G.

Lew

Richard,
I have replied to other similar threads over the years and sometimes people
listen and others do not, but I will repeat this advice again. Never connect
anything electrical to your hull, including a ground connection. If your
hull is not earth referenced, you will never suffer damage from a hot berth.
The cure is simple. Additionally, if your service DC is 12 volts, install a
red lamp in some location that is always visible and connect a 12 volt lamp
between your ship's battery to the hull. If your hull ever becomes shorted
to electrical earth, the lamp will be on indicating a short circuit
signaling you to take immediate action to resolve the fault.

The solution is simple on a boat you build, but isolating your hull when
someone else built it, can be a nightmare. No matter how much effort this
takes, the peace of mind this brings is worth it.
Steve

"richard" wrote in message
ups.com...
Same boat, same marina for 5 years-slightly different slip this year.
Boat stays in water 8 months out of the year (Boston harbor). always
have mechanic change zincs when winterizing (he says he did so this
year). discovered the prop had been destroyed by electrolysis as well
as damage to engine trims. never seen anything like this before
pulled boat our and had mechanic put new zincs on. Cost for haul,
wash, new zincs, labor and put back in water-$500 plus the cost of
replacing the prop. mechanic and I decided not to wait on engine trims
can anyone tell me more about what to do about the electrolysis? does
anyone think that this is something that could be covered by
insurance. have never made a claim on any of my boats over the year so
have no clue
thanks

On Thu, 11 Oct 2007 09:55:39 -0700, Joe
wrote:

he
sucked to many electrons from all his bronze hull fittings and and
shaft tube that they turned that brittle shade of pink.

That is sounds like the wholesale removing of the tin, zinc [in the
case of brass] or whatever leaving spongy pure copper. Brittle, that
wouldn't be, but it would be weakened.

Casady

On Oct 11, 3:48 pm, (Richard Casady)
wrote:
On Thu, 11 Oct 2007 09:55:39 -0700, Joe
wrote:

he
sucked to many electrons from all his bronze hull fittings and and
shaft tube that they turned that brittle shade of pink.

That is sounds like the wholesale removing of the tin, zinc [in the
case of brass] or whatever leaving spongy pure copper. Brittle, that
wouldn't be, but it would be weakened.

Casady

It looks like it transformed the bronze to a substance like cool lava
on a microscopic level, the bronze looses it shine and if you smack a
wheel that's pink.. it will find a fault and snap..the bronze is
indeed brittle almost chalkey . I'd have to look it up and see which
is more noble in a bronze mix to guess which electron's took a hike.

Electrolysis can do strange things. I've pulled 3" 25' SS shafts that
had what looked like big scoops of metal taken out..just like a red
hot ice cream scooper did it in butter..very clean, all purdy and
shiney.

I agree it's best to just isolate all wiring runs, use breakers,
fuses, and gauges to know whats going on.

Joe