Rewiring Question; Negative to the Water?

[hriehl1]

From another thread...

I agree. Bonding made sense in the past when shorepower and marinas were rare. In present times bonding the through hulls is an invitation for corrosion of an item that wasn't at risk before.

Here's a link to the best treatise I have come across relating to bonding.grounding by Stan Honey and reprinted from West Marine. It was also in Practical Sailor. http://www.sailmail.com/grounds.htm

OK... so I don't need the OEM bonding in the DC negative network. I'm rewiring the entire DC system and bringing all negative returns back to a common bus bar. That bus bar will also connect to the battery negative terminal. Is that all I need or does that negative-side circuit also need to find its way to water?

If so, what are methods used to get it to water when the power is an outboard setup? The prior bonding network served that purpose.

Thanks... Hank

[Ryan]

Unless you are attempting to put together some sort of lighting protection system, there is no need to add anything in contact with the water.

Keep in mind that unless you lift your outboard out of the water, it will connect your negative to the water anyway.

[mitiempo]

On an outboard powered boat the ground bus connects to battery negative. Nothing else is required or desired.

[Maine Sail]

An isolated ground system is fine and in many ways simpler and more reliable from a corrosion standpoint because you can lift your motor. With in-boards most of us don't have that luxury...

[Chris Campbell]

With in-boards most of us don't have that luxury...

Don't those rubber donuts you can put in your driveline (flex coupling) isolate them electrically as well as reducing jarring when you shift from forward to reverse or vice-versa?

[Ryan]

With in-boards most of us don't have that luxury...

Don't those rubber donuts you can put in your driveline (flex coupling) isolate them electrically as well as reducing jarring when you shift from forward to reverse or vice-versa?

You'll still need to take into account that the common stainless steel shaft/bronze prop combo will be subject to galvanic corrosion. Not a problem if you can tilt the motor out of the water!

[Maine Sail]

With in-boards most of us don't have that luxury...

Don't those rubber donuts you can put in your driveline (flex coupling) isolate them electrically as well as reducing jarring when you shift from forward to reverse or vice-versa?

If you're in salt water your engine is still "connected" to ground via the raw water intake system as you physically have "ground" in your engine unless you have a Marelon seacock that is closed.. ABYC does not however consider this a good ground and stipulates that if your engine is the ships ground, as most inboard engines are, a Drivesaver should be installed with a jumper or shaft brush to make a "proper" ground/earth path.

The marketing folks like you to think you can isolate your engine from the water with a Drivesaver but they apparently forgot you have sea water in your engine..

[Chris Campbell]

Interesting - and good to know! I hadn't thought of that, and will remember it when it comes time to redo electrical. Thanks!

[falcon]

What is the best way to fashion a "ground jumper" on an inboard with a drive saver, stainless shaft and bronze prop?