Diesel Engine Ground Question

[Thomas2222]

Hi Folks:
I'm new to the CF so let me know if I'm not posting my question correctly...
As a winter project I've been replacing all my single and double 0 battery cables throughout my sailboat. In the process I've discovered that the main ground (-) bolt on the engine is in turn connected by single 0 wire to a dedicated zinc on the outside of the hull. The zinc is pretty shot and needs replacing. But before I do this... I'm wondering if it is actually a good idea to have the engine bonded this way ? I've owned two previous sailboats and neither of them had any connection of this sort... Am I missing something...???

thanks for any thoughts you have.... Thomas...

[btrayfors]

Originally Posted by Thomas2222

Hi Folks:
I'm new to the CF so let me know if I'm not posting my question correctly...
As a winter project I've been replacing all my single and double 0 battery cables throughout my sailboat. In the process I've discovered that the main ground (-) bolt on the engine is in turn connected by single 0 wire to a dedicated zinc on the outside of the hull. The zinc is pretty shot and needs replacing. But before I do this... I'm wondering if it is actually a good idea to have the engine bonded this way ? I've owned two previous sailboats and neither of them had any connection of this sort... Am I missing something...???

thanks for any thoughts you have.... Thomas...

That's unusual. Zincs are normally attached to the shaft and sometimes other underwater metal fittings, and are intended to be sacrificial.

It's a good idea to have a single-point ground on a boat to which all grounded DC equipment is tied. Often this is a large bus bar located near the engine which, in turn, is itself connected to the engine.

For a dated but still excellent article on boat grounding see the piece by Stan Honey done for West Marine: Grounding

Bill