Just pulled my vessel out of the river, getting ready to take a trip
to one of the local lakes for a week-long vacation on-board. This
vessel has only been in the water for ~5 months, but the zinc anodes
look like they're working especially well. *THAT's* good news, but I
wonder if I shouldn't take a steel brush to 'em while I have the thing
out of the water. I'd much rather see the anodes rot than the
outdrive.

A bit of background, this is an 07 260DA and I keep it in the river
full-time, and it's connected to shore power while in the slip.

Thanks!

~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=

john burton
Bach 50B3 Bass Trombone
Kanawha Valley Community Band / Slide-by-Slide
South Charleston, West Virginia

wrote in message
...
Just pulled my vessel out of the river, getting ready to take a trip
to one of the local lakes for a week-long vacation on-board. This
vessel has only been in the water for ~5 months, but the zinc anodes
look like they're working especially well. *THAT's* good news, but I
wonder if I shouldn't take a steel brush to 'em while I have the thing
out of the water. I'd much rather see the anodes rot than the
outdrive.

A bit of background, this is an 07 260DA and I keep it in the river
full-time, and it's connected to shore power while in the slip.

Thanks!



I'd replace them.

wrote in news:45a41114-1908-4ca4-9625-
:

but I
wonder if I shouldn't take a steel brush to 'em while I have the thing
out of the water.

Nope. Just replace all of them.....

Zinc is LOTS cheaper than outdrive parts....

John,
Your sacrificial anodes for fresh water must be magnesium, not zinc.
Steve

wrote in message
...
Just pulled my vessel out of the river, getting ready to take a trip
to one of the local lakes for a week-long vacation on-board. This
vessel has only been in the water for ~5 months, but the zinc anodes
look like they're working especially well. *THAT's* good news, but I
wonder if I shouldn't take a steel brush to 'em while I have the thing
out of the water. I'd much rather see the anodes rot than the
outdrive.

A bit of background, this is an 07 260DA and I keep it in the river
full-time, and it's connected to shore power while in the slip.

Thanks!

~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=

john burton
Bach 50B3 Bass Trombone
Kanawha Valley Community Band / Slide-by-Slide
South Charleston, West Virginia

wrote
the zinc anodes look like they're working especially well.

In my experience, that's kind of unusual in the Kanawha. Could you have some
sort of stray electrical current problem in your slip?

You probably should be using magnesium anodes in freshwater.

Magnesium is less reactive than zinc; you are interconnected to ALL
OTHER BOATS in your marina since you (not such a good idea) keep the
AC connection at all times when you're in your slip. The problem will
be that if you are essentially bonded (via the AC ground) to another
boat(s) that does have magnesium, YOUR zinc will be the one that is
consumed since it is the least noble.
Consider to install a 'galvanic isolator' so that your boat is
'isolated' from that common AC ground wire !!!!!!!!!! ...... then get
a calibrated electrolysis cell (corrosion reference cell) and be sure
that you have the exact AMOUNT of anode needed for ***your specific
location*** for the best or most effective protection ........
http://www.boatzincs.com/corrosion-r...electrode.html. .... a
lot of good info is found on the www.boatzinc.com website.

Rich,
Please quit giving advise about things you do not understand. I am being
polite. You are misinformed. Please do your homework. There have many
discussions about this in the recent past.
Steve

"RichH" wrote in message
...
You probably should be using magnesium anodes in freshwater.

Magnesium is less reactive than zinc; you are interconnected to ALL
OTHER BOATS in your marina since you (not such a good idea) keep the
AC connection at all times when you're in your slip. The problem will
be that if you are essentially bonded (via the AC ground) to another
boat(s) that does have magnesium, YOUR zinc will be the one that is
consumed since it is the least noble.
Consider to install a 'galvanic isolator' so that your boat is
'isolated' from that common AC ground wire !!!!!!!!!! ...... then get
a calibrated electrolysis cell (corrosion reference cell) and be sure
that you have the exact AMOUNT of anode needed for ***your specific
location*** for the best or most effective protection ........
http://www.boatzincs.com/corrosion-r...electrode.html. .... a
lot of good info is found on the www.boatzinc.com website.

"RichH" wrote
you are interconnected to ALL
OTHER BOATS in your marina

No, I'm not.
I have a private dock on the same river as the OP.
He's the one in a slip.
And I believe you have your galvanic series backwards. Magnesium is more
anodic (less noble) than zinc, which is why it's typically recommended for
fresh water. The water being less conductive, a larger electrode potential
is desirable if you want to achieve similar protection.
When I had my powerboat in the Kanawha and was using zinc anodes, they'd
develop an insulating layer on their surface after a couple of weeks, taking
them out of circuit. Abrading them down to shiny metal would restore their
effectiveness, but it was a PITA, so I switched to magnesium. This reduced
the problem, but didn't totally eliminate it, and I still never saw
significant loss of material from my anodes, which is why I suggested to the
OP that he might have power issues.

On Wed, 20 Aug 2008 09:21:42 -0700 (PDT), RichH
wrote:

Magnesium is less reactive than zinc;

They used magnesium in incendary bombs because it will burn easily.
But it's less reactive? What zinc is, is cheaper. Aluminum is the
standard fuel in firecrackers, and my boat is aluminum. Spirit Lake in
Iowa has a number of aluminum boats originally bought by the no longer
there boat rentals of fifty years ago. The businesses are long gone
but the boats remain. None have ever seen a zinc or anything like it
unless it was perhaps built into an outboard moter. None of these
boats have shore power, most have no battery. No bronze thru hull
fittings. No corrosion in any of these boats in fifty years. Active or
not, bare aluminum boats don't seem to corrode even in sea water, at
least not withour help from dissimilar metals or shore power. We have
a magnesium ladder that has been out in the weather, hung for storage
on the outside of a shed, for fifty years. It got darker, is the only
sign of weathering.

Casady

Opppps, Brain Fart !!!

Zinc (-1.0v) less reactive than Mg (-1.6v).

Still the rest applies: galvalnic isolator, common bonding through the
AC ground, reference cell, etc., etc.