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agarabaghi
11-28-2011, 10:29 AM
So i think my lake is hot, and im seeing pit marks on my new prop already. I was going to attach some zinc to the shaft.

Does anyone know what size the shaft is on a 2006 X1...

Would something like this work?

http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=124021&catalogId=10001&langId=-1&storeId=11151&storeNum=50218&subdeptNum=50238&classNum=50241

MIskier
11-28-2011, 10:49 AM
Yes, that is exactly what you want, mount two of them on the shaft, one near the hull and one near the strut. the shaft is 1 1/8 dia.

agarabaghi
11-28-2011, 10:52 AM
Thanks! Ordering them now.

gotta_ski
11-29-2011, 02:10 AM
Is your lake fresh water or brackish? I'm no expert but I thought zinc was for saltwater and more active metals like magnesium were for fresh water. I think the zincs oxidize in fresh water, which makes them not work.

GoneBoatN
11-29-2011, 07:10 PM
Agar,

I beleve your boat sits in the water 100% of the time. You may want to check for stray currents in your boat and/or around your dock.

See http://www.boatzincs.com/corrosion-reference-electrode-specs.html?gclid=CO6E9bqE3awCFRLatgodFnZHrQ

GoneBoatN
11-29-2011, 07:16 PM
Found the following on the same web site:

http://www.boatzincs.com/pdfs/Chart_B-Which_Anodes_Should_I_Use.pdf and http://www.boatzincs.com/pdfs/Chart_A-Which_Anodes_Should_I_Use.pdf

-V-
11-30-2011, 07:54 AM
so why would you attach zinc? i seen it a lot on ship shape tv, but never knew why.

GoneBoatN
11-30-2011, 12:17 PM
so why would you attach zinc? i seen it a lot on ship shape tv, but never knew why.

The following has good explainations:
http://delreymarina.com/assets/files/galvanic-corrosion.pdf
http://www.boatsurveyor.com/Articles/prevent_corrosion.htm

I remembered Agar's post on his broken prop which had pictures of his strut and rudder. At the time I thought it might be an explaination for how they looked. See http://mastercraft.com/teamtalk/showthread.php?t=44593.

wakescene
11-30-2011, 12:57 PM
Check your battery grounds as well. If they are good, you will minimize the effects of electrolysis pitting and corrosion if you suspect your lake is hot.

agarabaghi
11-30-2011, 02:46 PM
The dock has power, and I think it's from that. Not sure though.

http://www.boatzincs.com/shaft1-magnesium-sizes.html

So those would be better for my application?

Reverend Bob
11-30-2011, 03:05 PM
This is a very good link to the wonders of electrolysis, might be of some help.

http://www.yachting-life.net/new%20index/frames3/electrol_frame.htm

GoneBoatN
11-30-2011, 06:22 PM
At that same site look under the FAQ at http://www.boatzincs.com/faqs.html.

There is a section - "Q: Which anodes should I use: Zinc, Aluminum or Magnesium?" and has a couple links to two tables and it should help guide you. I also read in those tables that it is bad to have two different types installed. So for example if you have the drain plugs that have zinc anodes attached then Magnesium would be bad. Generally they are only in boats for saltwater from what I understand. So from the charts at the url above I would assume magnesium. I used the word assume intentionally. It's not like I'm an expert on this but rather what little I know from my old I/O which because of the all the zinc's it had on it plus it had the option of an galvanic isolation device; add to that some fast research via google searches. So that's my disclamer. :D

In those tables you will see note (2 or 8 depending upon which chart) -
The underwater metals on fiberglass inboard vessels are usually stainless steel and bronze attached to the vesselís bonding system. Use zinc or aluminum anodes, but donít mix types if bonded together. In freshwater, use more active aluminum or magnesium anodes for self-cleaning performance.


I think you are looking for the "self-cleaning performance" per above.

That little device in my first post would certainly tell you if it is from your dock. I take it there are other boats near by with shore power?

GoneBoatN
11-30-2011, 06:54 PM
This is a very good link to the wonders of electrolysis, might be of some help.

http://www.yachting-life.net/new%20index/frames3/electrol_frame.htm

Definitely good reading. Which brings up a good point. The rudder. Is a separate sacraficial anode needed for the rudder as well or is it connected enough not to require one. :confused:

The signature of another poster on another message board read "any grease is better than no grease". Perhaps that applies here.

I also just noticed "Propeller Nut With Magnesium Anode" - http://www.boatzincs.com/prop_nut_magnesium_specs.html. They also have anodes for the rudder.

thatsmrmastercraft
11-30-2011, 07:21 PM
Amazing what a person can learn here.:popcorn::popcorn::popcorn:

MIskier
11-30-2011, 07:37 PM
Definitely good reading. Which brings up a good point. The rudder. Is a separate sacraficial anode needed for the rudder as well or is it connected enough not to require one. :confused:

The signature of another poster on another message board read "any grease is better than no grease". Perhaps that applies here.

I also just noticed "Propeller Nut With Magnesium Anode" - http://www.boatzincs.com/prop_nut_magnesium_specs.html. They also have anodes for the rudder.

Yes another is required on the rudder to fully protect the boat, and it does require drilling the rudder.

I would try to take a look at how the dock is grounded first though.

Reverend Bob
11-30-2011, 08:03 PM
As mentioned, the boats' surroundings need a bit of analysis if she is in the slip full time. Struts, rudders, shafts, can be fitted with zincs, or mounted on the transom. There are bonding methods for the running gear, in which the rudder housing, strut, and shaft are grounded together by means of a strap/wire, to the engine, as well as any through hull fittings.

Then there is a condition referred to as "over-zinc-ing", but I'll leave that one alone!

GoneBoatN
11-30-2011, 09:53 PM
Yes another is required on the rudder to fully protect the boat, and it does require drilling the rudder.

I would try to take a look at how the dock is grounded first though.

Finding the source of the problem is always best if/when it can be done. It's that darn prevention vs cure thing. One note I found in one of the articles is that it could be as simple as a car charger being used in a boat causing the stray current... Funny how if you first look for the simple and common things you tend to find them.

Yet more reading: http://marinesurvey.com/yacht/corrosion_2.htm

I know, we need a new government agency - the Galvanic Corrosion Detection Agency. No,that doesn't work. There must be some name to derive a good acronym.

GoneBoatN
11-30-2011, 09:54 PM
...there is a condition referred to as "over-zinc-ing", but I'll leave that one alone!...

Kill-joy :D

How did we ever get along without the smilies during the website upgrade???

agarabaghi
12-01-2011, 07:46 AM
I don't think the HOA will allow me to "inspect" and change anything on the dock. They are kind of dock nazi if you know what i mean. As far as I know none of the boats actually use the power, but there are lights on the dock that come on at night.
Im pulling the boat out tomorrow, and im going to take pictures of the "corrosion". It doesn't look like anything in the pictures. Once ive cleaned it all off, Im going to attach the zinc anodes since I have them, and let the boat sit for a week and then pull it out again and see if the "corrosion" has returned.
Im assuming I can sand off the "bumps" from the brass with a light sand paper... it seems to have worked in the past and not damaged the brass.

GoneBoatN
12-01-2011, 11:58 AM
I went back to read your post about the broken prop. No known explanation of how it happened (did not hit anything, etc). I wonder if this could contribute to enough metal fatigue to be the reason. Maybe something to ask OJ about.

I would think that if you found stray current in the water, especially if it happens when the lights are on but not when they are off, then the HOA would have to do something about it. However, some of the information indicated that AC contributed far less to the corrosion than DC. It appears that DC and the conversion to DC is a large part of the culprit.

I would think getting some sacrificial anode on it would be prudent. Then you can tell if starts to be consumed.

As suggested before, checking the dock ground may be a good idea. Should not be too hard. No one should even notice.

bobx1
12-01-2011, 12:36 PM
If there is a current from anything provided by the HOA then they have a liability on their hands.

Watch how quick marina owners react when someone tells them there is a stray current in the water.