mick
Member
Does it make sense to have a wire running from the battery negative to the raw water seacock?
Battery to seacock?
- Thread starter mick
- Start date
aidancoughlan
Member
dont know, but It might be something to do with 'bonding', connecting all the metal parts of the boat to the anode... there are wires running from my seacock in the engine compartment to the aft sections, I think to the anode.
mithril
Member
Its never easy to answer this type of question without seeing the installation, so be wary of over confident replies.
However, the above comment not withstanding, all skin fittings which are close together can be joined together and locally provided with a sacrificial anode. Skin fittings, which are far removed from the previously described group, should not be connected to the group but should have a local anode.
So to your question,
- if the seacock has no anode then give it one locally.
- battery negative, I think this is an irrelevance and need not be connected to any of your seacocks especialy if they have a local anode.
One thing is true, come lift out all will be revealed. The anode(s) should be slightly eroded and if they are not then one of the skin fittings will be, even if you cannot see it immeadiately. /forums/images/graemlins/smirk.gif
However, the above comment not withstanding, all skin fittings which are close together can be joined together and locally provided with a sacrificial anode. Skin fittings, which are far removed from the previously described group, should not be connected to the group but should have a local anode.
So to your question,
- if the seacock has no anode then give it one locally.
- battery negative, I think this is an irrelevance and need not be connected to any of your seacocks especialy if they have a local anode.
One thing is true, come lift out all will be revealed. The anode(s) should be slightly eroded and if they are not then one of the skin fittings will be, even if you cannot see it immeadiately. /forums/images/graemlins/smirk.gif
tim3057
New member
I thought I might 'earth' all my skin fittings to battery negative as I'm told this stops any stray current leaching back through them? Is this not right?
boatmike
Well-known member
You could do more harm than good.
If the seacock is bronze it needs no protection. If it is a brass containing zinc it could well become an anode rather than a cathode if so connected which is dangerous. The safest thing (assuming its a GRP boat) is, regardless of common folk lore and practice, to make sure all fittings are bronze and don't ground them to the battery.
Protect your prop and any other vulnerable fittings with an anode and bond them all together by all means but if you do this ensure the circuit is not connected directly to battery negative and don't connect the propshaft to the engine with an earthing strap across the flexible coupling.
If the seacock is bronze it needs no protection. If it is a brass containing zinc it could well become an anode rather than a cathode if so connected which is dangerous. The safest thing (assuming its a GRP boat) is, regardless of common folk lore and practice, to make sure all fittings are bronze and don't ground them to the battery.
Protect your prop and any other vulnerable fittings with an anode and bond them all together by all means but if you do this ensure the circuit is not connected directly to battery negative and don't connect the propshaft to the engine with an earthing strap across the flexible coupling.