Egregious
Guru
The last time I had my shaft zincs changed I noticed that one of them was not degraded at all. I believe the problem is that the shaft isn't bonded to the rest of the system. On one side I have a wire that connects the shaft to the transmission which jumpers the two together where a plastic shaft saver is separating the two. This wire broke on the other side. Until I can get this fixed I just used a wire with battery clips on both ends to temporarily connect the shaft to the bonding system when not under way.
I was curious about what kind of current would flow between the shaft and the bonding system, so I put a multi tester on it and I'm reading about .25 volts flowing between the transmission and the shaft. That means the red lead on the transmission and black lead on the shaft. I get the same if I place the red lead on a nearby thru hull fitting which is bonded to the rest of the system. Turning off all electrical systems, battery switches, breakers, and main 120V switch has no effect, but physically unplugging the shore power cord reduced or eliminated the voltage flow.
I do not have a galvanic isolator.
In addition, my boat has three steel (I assume) pilings in the general vicinity, and I understand that the galvanic incompatibility leads to an electric current.
Do I have stray power entering the boat via the ground of my shore power or is this normal galvanic corrosion and the zincs are doing their job by degrading?
I was curious about what kind of current would flow between the shaft and the bonding system, so I put a multi tester on it and I'm reading about .25 volts flowing between the transmission and the shaft. That means the red lead on the transmission and black lead on the shaft. I get the same if I place the red lead on a nearby thru hull fitting which is bonded to the rest of the system. Turning off all electrical systems, battery switches, breakers, and main 120V switch has no effect, but physically unplugging the shore power cord reduced or eliminated the voltage flow.
I do not have a galvanic isolator.
In addition, my boat has three steel (I assume) pilings in the general vicinity, and I understand that the galvanic incompatibility leads to an electric current.
Do I have stray power entering the boat via the ground of my shore power or is this normal galvanic corrosion and the zincs are doing their job by degrading?