Bonding thru hulls

[Franklin]

I've been reading up on electrolysis and all the articles I've read says that all the metal that touches the water has to be bonded together so they will be protected by the zincs on the prop. My H376 doesn't have anything bonded except the mast to a keel bolt. Why doesn't hunter bond the thru hulls? It's not like it's a cost cutting measure.

 

[Bill Roosa]

You don't need to

You need to either bond everything or unbond everything. Unbonding is cheeper and helps with the lightning grounding. You don't want a gazillion amps going through a thru-hull.As long as the thru-hull is not made of 2 or more metals you will be fine. A SS prop shaft and bronze prop will still need a zinc however.

 

[Franklin]

Bill...you are correct.

"Keep in mind that this approach involves an increase in the danger level if there is an electrical fault. There is a possibility that if a short circuit develops somewhere between the AC supply and the 12 volt system, it will not trip the circuit breaker and leave things like the engine block and DC equipment alive. If you take this route it is important to make sure your rigging is NOT connected to the bonding circuit as this could theoretically put dangerous voltages on the rigging. "Seems Hunter doesn't bond the thru hulls and rigging because they also don't connect the green wire to the DC ground at the engine. They do install good circuit breakers right at the shore power connectors so that is good.

 

[Cap'n Ron]

Dichotomy Dictates Delemma

You are both right.Franklin, I have been following your posts on this subject when I could, and you have done mucho work following these little gimlin-devils all through yer bilge etc.They use 'silver nitrate' and long leads to test for a ground fault, and bonding is tested but there is a huge controversy foing on by some world reknown experts on this exact subject on another forum, and the consensus, well there is no real consuesus except that the most knowledgable fellow I know says DO NOT bond through-hull fittings!There is one that all agree on though: if you change your through-hulls to Marlon you will have no further trouble with electrolysis nor the freezing of the ball-valve handle.