Re: carb help
It's the same thing:
Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially when in electrical contact with a different type of metal and both metals are immersed in an electrolyte. Conversely, a galvanic reaction is exploited in primary batteries to generate a voltage. A common example is the carbon-zinc cell where the zinc corrodes preferentially to produce a current. The lemon battery is another simple example of how dissimilar metals react to produce an electric current.
It's either called electrolysis or galvanic corrosion, I mislabeled it as electrolysis corrosion.
Aluminum can be used, but you need to coat the water passages or use a fresh water cooling system. I've heard of people coating the waterways with a thinned down mixture of JB Weld and alcohol before.
Hardly the same. Question. If both processes are the same, why two different names?
Galvanic Corrosion
Galvanic corrosion occurs when two dissimilar metals form a natural battery when placed in contact with each other while immersed in an electrolyte. Seawater is a perfect electrolyte for metals. Metals vary in their reaction to being part of this natural battery. Metals that are more active are anodes or less noble. In a galvanic cell a less noble metal, like zinc, will dissolve sooner a more noble metal like brass. Prevention includes proper choices for metals used in vessel construction, use of protective paints and sacrificial anodes.
Electrolysis
Electrolysis is also the corrosion of dissimilar metals, but a different process causes it. A difference in the direct potential current that exists between two dissimilar metals is the reason for the problem. This is a stray current or circuit that is not following an anticipated path. Improper wiring, poor choices in building materials, or defective electrical appliances can cause it. Introduced currents will flow by the path of least resistance. Stray current can also cause Electric Shock Drowning.
Electrolysis is much more destructive to boats than galvanic corrosion. You can reduce electrolysis with these ideas:
?Avoid the use of common automotive battery chargers on your boat. These chargers use an auto transformer in which the primary and secondary windings are electrically connected. Marine battery chargers use an isolation transformer. An isolation transformer has separate windings and does not allow current to pass into the vessel from the utility connection
?Vessels using a positive ground electrical system should avoid mooring next to one with a negative ground system
?Check the connections to any two bilge pumps that are electrically connected. Ensure that each pump shares the same positive and ground connection. If one pump is grounded to the frame and the second is not, a stray current will be introduced
?Electric welders can introduce current into salt water due to frayed or damaged connectors. If welding is required on a vessel, it is better if the welder is mounted on the boat being welded
?Check your vessel for reversed polarity
?Check to see if any severe corrosion is present near telephone connections. Telephone service voltage can introduce 48 volts of current into the water
?Install sacrificial zincs on your boat and properly maintain them
?Keep a layer of quality bottom paint applied to all hull surfaces in contact with the water
?Tilting your outboard motor out of the water may completely eliminate corrosion
"JB Weld and alcohol"
Be careful what you listen to. This is as good as the "magnetizing water".
