Boat sunk at marina

[cv23]

Sorry but you are wrong.
Not this time sunshine.
Electrolysis has nothing to do with a moving boat or static electricity, it is a natural process between dissimilar metals and can be greatly exasperated by man induced electricity.
Wrong, you are confusing galvanic corrosion with electrolysis
This process happens in all environments (including air) but is fastest in an environment surrounded by an electrolyte such as salt water.
But you said fresh water marinas were worst?

Sacrificial anodes (zincs) are attached to metal components that are electrically bonded inside the boat, such as a prop shaft or the cutlass or rudder. If it's a plastic or non-conductive hull, there is no need of zincs. if you have an outboard then of course it should be fitted with zincs.
Most sail boats have kickers and all the rest have motors so other than one person sail boat all boats have sacrificial anodes.


Depending on the marina and season I replace my zincs on average every three months. My boat has a stainless prop shaft, an aluminum cutlass, fibreglass rudder with stainless shaft and bronze through-hulls, and for the last year my boat has been a dock-condo and hasn't moved more than ten miles, but the zincs still get eaten at the exact same rate.
You are in saltwater so as I said the process happens far more quickly than in fresh water and would happen even faster if the boat was moving due to the static electrical charge created as it moves through the water.

By your theory only fibreglass boats would suffer from electrolysis and therefore require zincs, but a steel boat will have very large and numerous zincs bolted on to its hull.
You said it happens when disimilar metals touched which is galvanic corrosion not electrolysis so of course a steel boat would be effected and to even far greater effected because they are metal rather than fiberglass
Aluminum hulls require paint or primer everywhere on the inside of the hull, as a single penny or steel washer will eventually burn a hole through thew hull if unchecked.
You are confusing galvanic corrosion with electrolysis again

Galvanic corrosion (also called ' dissimilar metal corrosion' or wrongly 'electrolysis') refers to corrosion damage induced when two dissimilar materials are coupled in a corrosive electrolyte.

http://corrosion-doctors.org/Forms-galv ... rosion.htm

[cv23]

I have to disagree with you on another point, and that is that "Most boats made since the 60's have sacrificial anodes". I have owned many fresh water power and sail boats since the 70's and I can't recall one being fitted with a zinc. I also own and live on a salt water vessel and every one is fitted with numerous zincs (sacrificial anodes). It would never hurt to have a zinc mounted on your fresh water boat, but all metal components touching water need to be electrically bonded to that anode or it's of no use.

I worked at a marina/marine dealership for years and held a Mercuiser mech certification. All Mercs both old and new, fresh and saltwater applications, have sacrificial anodes. They are attached directly to the drive or by a single wire and located in various places. Today Merc includes both sacrificial anodes and an electrical cathode system to deal with corrosion related issues.
http://chemistry.about.com/od/electroch ... athode.htm

[g802]

If you knew me you most definitely wouldn't call me sunshine, but I do live in sunshine year round.

I have to give you the difference between galvanic corrosion and electrolysis, the penny on a aluminum hull would be galvanic corrosion.

I said that (according to experts) a human body will conduct electricity better than the fresh water and therefore, more likely be electrocuted. That statement had nothing to do with corrosion.

I guess I will never convince you that the zincs don't last any longer sitting at the dock then when the boat is moving through the water. That alone should put your static electricity theory to rest. I will ask around if anyone has ever got a static shock while on their boat, maybe the owners of the cement hulls.

Where I am most sailboats don't have kickers except on the dinghy's, they have diesel engines. Fresh water sailboats frequently have kickers, maybe that is what your talking about.

[g802]

[quote="cv23"]
I worked at a marina/marine dealership for years and held a Mercuiser mech certification. All Mercs both old and new, fresh and saltwater applications, have sacrificial anodes. They are attached directly to the drive or by a single wire and located in various places. Today Merc includes both sacrificial anodes and an electrical cathode system to deal with corrosion issues.
http://chemistry.about.com/od/electroch ... athode.htm[/quote]

That's wonderful and I am glad you are employed. I said the fresh water outboards I have owned in the past, where never fitted with zincs. My Johnson 15hp kicker on my dinghy has two zincs mounted on the lower leg because it is used in salt water. Maybe all the new motors produced and sold for fresh water usage are now equipped with zincs, I don't know and I don't care. The motors I have owned in the past were never fitted with zincs.

http://www.boatus.com/boattech/articles ... rosion.asp

There is lots of information regarding this, but I am sure most of it would never amount to much with a fresh water boat, such as you are working on and around.

[Monsterdriver]

G802

I looked up on the internet and I have read what your talking about. Mariners do use the terms galvanic corrosion in conjunction with electrolysis, and I think that is where you two differ. cv23 is a wrench puller and you are a mariner, he plays in fresh water and you sail on the sea.

He totally misquoted you about a person being electrocuted in "fresh water".

I haven't found anything serious about static electricity in regards to anodes on a boat, maybe something about a pump operating on a boat, but not directly related to the boat.

Furthermore, I can't believe you are arguing with a clown.

[cv23]

He totally misquoted you about a person being electrocuted in "fresh water".

A common problem is electrolysis, created either on your boat, the one next to you, or marina wiring. This can cause a through-hull, bolt or inside fitting to burn through very quickly, if there is sufficient electricity leaking. This is also the reason to never swim in a marina, especially a fresh water marina.

Misquoted???? LOL
You need to understand the physics of electron movement and just what the differences are between galvanic corrosion and electrolysis before you post much more incorrect information. FYI electolysis in water is the decomposition of water (H2O) into oxygen (O2) and hydrogen gas (H2) due to an electric current being passed through the water, Sorry to tell you two its nothing to do with dissimilar metals as that is galvanic corrosion a totally different reaction of electrons.
This is all covered in Mercury Marine tech certification.

[g802]

Maybe that's why the diver (cleaning the bottom) reports back when he sees the prop or a through-hull foaming (creating bubbles), or do you think those are bronze bubbles? LOL!!!

Maybe us dumb sailors and dock folk don't know the ins and outs of a Mercury outboard, but we do know foaming bronze is caused from stray current.

Maybe that's why you rarely see a Mercury outboard out on the salt, they don't last or are poorly maintained.

Maybe we don't have the terminology 100% correct all the time, but we all know what the other person is referring to, and try to help. That apparently is the biggest difference between salt and fresh water.

Good luck with your career choice.

[Monsterdriver]

You need to understand the physics of electron movement and just what the differences are between galvanic corrosion and electrolysis before you post much more incorrect information. FYI electolysis in water is the decomposition of water (H2O) into oxygen (O2) and hydrogen gas (H2) due to an electric current being passed through the water, Sorry to tell you two its nothing to do with dissimilar metals as that is galvanic corrosion a totally different reaction of electrons.
This is all covered in Mercury Marine tech certification.

cv23 you need to seek an education outside of those Mercury manuals, maybe a college science course or even high school. You do know those company courses are usually compiled by the same type of wrench puller as yourself.

You are taking a small kernal of fact and supporting your entire theory behind it. The fact is that O2 and H2 are a product of the electrolysis of water. There is a whole lot of other things going on if you are not talking about pure water.

"The key process of electrolysis is the interchange of atoms and ions by the removal or addition of electrons from the external circuit. The desired products of electrolysis are often in a different physical state from the electrolyte and can be removed by some physical processes. For example, in the electrolysis of brine to produce hydrogen and chlorine, the products are gaseous. These gaseous products bubble from the electrolyte and are collected.[3]

2 NaCl + 2 H2O → 2 NaOH + H2 + Cl2"

http://en.wikipedia.org/wiki/Electrolysis

Electrolysis is used in electroplating (transfer of metal), reduction and purification of metals, production of compounds, etc etc.
You're the one that needs to expand your knowledge base beyond your company literature, as it appears to be very, very focused. I assume they want to want to push the potential technicians through the company course in a week or two. A licensed mechanic is a four year trades qualification and the course would be recognized by the province.

There is an old saying:
" The dog with the smallest bone, is usually the most aggressive in the pack"

[cv23]

cv23 you need to seek an education outside of those Mercury manuals, maybe a college science course or even high school. You do know those company courses are usually compiled by the same type of wrench puller as yourself.

You are taking a small kernal of fact and supporting your entire theory behind it. The fact is that O2 and H2 are a product of the electrolysis of water. There is a whole lot of other things going on if you are not talking about pure water.

"The key process of electrolysis is the interchange of atoms and ions by the removal or addition of electrons from the external circuit. The desired products of electrolysis are often in a different physical state from the electrolyte and can be removed by some physical processes. For example, in the electrolysis of brine to produce hydrogen and chlorine, the products are gaseous. These gaseous products bubble from the electrolyte and are collected.[3]

2 NaCl + 2 H2O → 2 NaOH + H2 + Cl2"

http://en.wikipedia.org/wiki/Electrolysis

Electrolysis is used in electroplating (transfer of metal), reduction and purification of metals, production of compounds, etc etc.
You're the one that needs to expand your knowledge base beyond your company literature, as it appears to be very, very focused. I assume they want to want to push the potential technicians through the company course in a week or two. A licensed mechanic is a four year trades qualification and the course would be recognized by the province.

There is an old saying:
" The dog with the smallest bone, is usually the most aggressive in the pack"

Where did the boat in question sink, in the salt water ocean or a fresh water lake?
As far as trade qualifications go what are yours with regard to marine mechanics?

[cv23]

Maybe we don't have the terminology 100% correct all the time, but we all know what the other person is referring to, and try to help. That apparently is the biggest difference between salt and fresh water..

Where did the boat which is the topic of this discussion sink, in the saltwater ocean off Mexico or the fresh water of Okanagan Lake? What good is incorrectly stated info about boats in saltwater have to do with boats in freshwater.
FYI Mercury Marine is the largest marine propulsion company in the world and widely recognized as the leader in marine propulsion technology.

[Monsterdriver]

Mercury Marine is one of the largest marine propulsion companies in the world, not the largest.

Boats sink for exactly the same reason in fresh or salt water, gravity becomes greater than buoyancy. Fourteen boats sinking at KYC in one season does seem excessive, how does this compare to other years? What kind of boats (ski, sail, cabin) were they?

[cv23]

Mercury Marine is one of the largest marine propulsion companies in the world, not the largest.

Please name a marine propulsion company larger than Mercury Marine.

[Monsterdriver]

So then what is the largest marine propulsion company in the world ?

They don't say which is the largest, just that Mercury Marine is "one of the largest".

http://en.wikipedia.org/wiki/Mercury_Marine

I was surprised that Tohatsu builds all of their smaller motors and that their midsize motors are all made in China. I think I will stay with Honda.

[cv23]

I think I will stay with Honda.

Honda Marine only makes outboards up to 250hp. They do not make sterndrives, inboards or marine diesels
The 30' boat that recently sank in KYC was not outboard powered.

[Monsterdriver]

My small pusher is a Honda and my inboard has twin Volvo diesels.
Does anyone else make sterndrives besides Volvo, Mercruiser and I think Yamaha?