electrolysis

[DiamondHead]

Hi,
I had a bad experience which I would like to share for the benefit of the forum readers. I hauled my boat last april for normal routine maintanance, but I was shocked to see how corrosion ruined my props completely. Last time I used the boat was in Febraury and everything was perfect. So I tried to gather as much information as possible to understand what had gone wrong. There was nothing wrong with the boat, and I was convinced that the current came thorugh the shore supply. But to my surprise, I discovered that all the trouble came from a faulty alternator. The alternator was absorbing 10amps and since it was short circuit, the props acted as anode after the zinc ones had been consumed in less that a fornight. Be careful guys.
Regards
Joe

 

[William_H]

If the boat(props) was fine in Feb and now bad does this mean that you think the alternator was the cause even though it was not rotating.
Do you mean the power was on the field coil all that time and how did that cause prop damage.
Can you please explain the current paths etc that caused the corrosion.
olewill

 

[DiamondHead]

Hi,
Actually the field coils developed a short circuit to earth and current was continuously flowing about 10amps. first finished the zince anode and then started eating the props.
Now the alternator has been removed and current stopped.
Hope this answers your question.