Anodes ???
 

I boat on the hudson river, it's for the most part fresh water where we boat and I believe I have alum. anodes. The boat probably sat in the water for a total of 2 months on and off, in 2 weeks out 1 for the entire season, my anodes are in perfect shape, shouldn' they have atleast decayed somewhat ?? some say the water is brackish, maybe at hight tide it could be but I still believe its for the most part fresh.. The paint on the drive is fine, but a tiny bit pitted around the top cap.. This has me concerned which are the correct anodes ??

Re: Anodes ???
 

In freshwater, your best bets are either aluminum or magnesium.
In Salt, zinc is best.

Maybe there's more salt in your area than you think, or perhaps there is some stray current from a nearby boat.

Re: Anodes ???
 

Maybe you didn't have a lot of electrolysis?

If you had the "wrong" anode, the drive would become sacrificial, rather than the anode.

Plus, maybe you aren't mixing metals much.
Maybe you aren't using shore power much, or docking next to a steel hull (that screwed me one year, pulled out an alpha that was half gone!)

Somebody correct me if I'm wrong, but these days they are using Magnesium for fresh, yes?

Re: Anodes ???
 

Maybe try a zinc? See how brackish it really is?

Re: Anodes ???
 

If you are plugged into a 3 wire shore power cord on a dock with other boats, nothing will help you. You are bonded to the other guys on the dock, and are protecting their bronze props with your aluminum drive. If that is the case, you are doing all that you can do.

Re: Anodes ???
 

I dont have shore power, and when I asked sunsation about different anodes, they said whatever came with the drives,, them being in michigan I assume and they look to be alum. for fresh water. My wife used to keep her boat a lot farther south, where it truely was brackish / saltier, her anodes usually lasted 2 seasons of being in 24/7 for 6 months and she used zinc. 26 sonic from the board went through 2 lowers in the marina up the river from me, but turned out his mercathode wasn't hooked up correctly, so I understand that.. just surprised the anodes aren't atleast a little eroded...

Re: Anodes ???
 

Especially since nothing else is.

I had good luck this year, hardly any pitting or anything at all.
But I have OMCs. Resistance to electrolysis is one of their few strong points.

Re: Anodes ???
 

If the water is fresh... there isn't the "medium" for the electrolysis... you will find the salt acts like an electrolyte.. much like the acid in a battery. So... the "least noble" metal protects the most... where salt water is... Zinc works well.. . but you have to clean them off often... in fresh water use magnesium... they offer the most protection in a water that is absent of electrolytes... but... if you put the magnesium in salt water... they won't last long at all... If you are next to people with a metal hull with shore power and in salt water.... It won't matter what anode you have.... your alloy parts in the water are going to suffer. Some engines have a provision for a pencil anode that goes where the drain plug was. If you are mostly in fresh water... don't let it worry you too much.

Re: Anodes ???
 

If you are in salt water at all... there are some crazy things that happen... if you have any steel touching alloy directly... there will be pitting underneath... for example... The trim indicator mounts on the tilt rams... I found wrapping them with electrical tape to isolate the metals worked well... but I had zinc anodes on EVERYTHING alloy on the stern. I had them on the trim tabs, gimbal housings, tilt rams, steering rams, outdrives, trim tab mounts, you name it... Even after washing and never leaving the boat in salt water for more than a few hours at a time.... the anodes were incredibly pitted at the end of each year. The other thing to remember is the anodes have to be mounted on a clean bare surface.. they must contact the metal they are protecting.. and periodically they must be removed and the mating surfaces cleaned for a good "connection"... :D

Re: Anodes ???
 

Thanks Reedy... :)

Re: Anodes ???
 

OK, now you've confused me, which isn't hard I know, is there such thing as an aluminum anode??? The whole point of anodes is to have a metal in contact with your existing hardware that is less noble causing it to corrode first. What would be the point of putting an aluminum anode on an aluminum drive??

Re: Anodes ???
 

The aluminum anode is left bare to dissolve... the rest of the part is painted. :D

Re: Anodes ???
 

I'll post an anode chart.... the metal on top protects the metals below it.
GALVANIC SERIES OF METALS AND ALLOYS
CORRODED END ( ANODIC OR LEAST NOBLE)
MAGNESIUM
MAGNESIUM ALLOYS
ZINC
ALUMINUM 5052, 3004, 3003, 1100, 6053
CADMIUM
ALUMINUM 2117, 2017, 2024
MILD STEEL (1018), WROUGHT IRON
CAST IRON, LOW ALLOY HIGH STRENGTH STEEL
CHROME IRON (ACTIVE)
STAINLESS STEEL, 430 SERIES (ACTIVE)
302, 303, 304, 321, 347, 410,416, STAINLESS STEEL (ACTIVE)
NI - RESIST
316, 317, STAINLESS STEEL (ACTIVE)
CARPENTER 20CB-3 STAINLESS (ACTIVE)
ALUMINUM BRONZE (CA 687)
HASTELLOY C (ACTIVE) INCONEL 625 (ACTIVE) TITANIUM (ACTIVE)
LEAD-TIN SOLDERS
LEAD
TIN
INCONEL 600 (ACTIVE)
NICKEL (ACTIVE)
60 NI-15 CR (ACTIVE)
80 NI-20 CR (ACTIVE)
HASTELLOY B (ACTIVE)
BRASSES
COPPER (CA102)
MANGANESE BRONZE (CA 675), TIN BRONZE (CA903, 905)
SILICONE BRONZE
NICKEL SILVER
COPPER - NICKEL ALLOY 90-10
COPPER - NICKEL ALLOY 80-20
430 STAINLESS STEEL
NICKEL, ALUMINUM, BRONZE (CA 630, 632)
MONEL 400, K500
SILVER SOLDER
NICKEL (PASSIVE)
60 NI- 15 CR (PASSIVE)
INCONEL 600 (PASSIVE)
80 NI- 20 CR (PASSIVE)
CHROME IRON (PASSIVE)
302, 303, 304, 321, 347, STAINLESS STEEL (PASSIVE)
316, 317, STAINLESS STEEL (PASSIVE)
CARPENTER 20 CB-3 STAINLESS (PASSIVE), INCOLOY 825
NICKEL - MOLYBDEUM - CHROMIUM - IRON ALLOY (PASSIVE)
SILVER
TITANIUM (PASS.) HASTELLOY C & C276 (PASSIVE), INCONEL 625(PASS.)
GRAPHITE
ZIRCONIUM
GOLD
PLATINUM
PROTECTED END (CATHODIC OR MOST NOBLE)

Re: Anodes ???
 

Thanks again Reediddy...

Re: Anodes ???
 

Reed you are totally right, and you were paying attention in chemistry class.

But, there's fresh water, and then there's clean water.

There is some pretty nasty fresh water around where I live. Like the river with the 100 years of Jeep plant pollution that I used to keep my boat in.
It was brown and would turn my stainless cloudy in a day. The clams glowed in the dark.

There was one heck of a lot of "medium" for electrolysis in that "fresh" water.
:D

Re: Anodes ???
 

So, What anode comes standard on the Merc Bravo drives? Or is this the discretion of the builder?

Re: Anodes ???
 

Probably zinc..... zinc will protect in any water.... for fresh water, magnesium is better... If you were to put magnesium anodes on in salt water... they would protect too... but would dissolve quickly.

Re: Anodes ???
 

Oh yeah... I forgot... you're in Toledo... where the Maumee catches on fire..... :eek: ( my ex-wife was from Toledo )......... :eek:

Re: Anodes ???
 

Is she hot? Did she move back? :D

Re: Anodes ???
 

Uhhhh.... dunno.... I haven't seen her in 20 years.... but I heard she is still living in SLC.... but her family name is .......... Penske............ :eek:

Re: Anodes ???
 

I was supposed to go to SLc next week but I got out of it.

:D

Re: Anodes ???
 

How the heck did my Anodes thread get turned into the love connection ??? :D

I would be awfully leery of Reediddy's X.. haven't you noticed how cynical the man is ?? seems he's been raked over the coals a few times..

Re: Anodes ???
 

yeah. sorry about that.

I've pulled more hijackings lately than a Cuban in the seventies.

Re: Anodes ???
 

LMAO,,, No problem Fund,, just busting balls.. :p :D

Re: Anodes ???
 

Some good reading:

http://www.boatus.com/seaworthy/galvanic/default.asp

http://www.boatus.com/boattech/MarineCorrosion.htm

http://www.boatus.com/boattech/Casey/23.htm

Re: Anodes ???
 

Me? raked over the coals?.. no .. not me.... I get dragged ONTO the coals.. and then left there until I'm a blackened fricasee........ :D