Connecting anode to stern gland, right or wrong?

[jerrytug]

Does anyone know if this wire should be there, I haven't seen anything like it before. Yacht is glassfibre, conventional Yanmar installation, bronze prop, stainless steel shaft.
Is the wire in the photo

A) Right.
or,

B) Wrong.


Thanks for your expertise Jerry

 

[prv]

Presumably it's an attempt to connect the anode to the shaft. An attempt doomed to failure if the bearing is the standard rubber cutless type, which the water inlets to its housing suggest it is. The wire won't be doing any harm as far as I can see, but it's unlikely to be helping. The connection from anode to shaft would more conventionally be made on the inside of the hull, from the anode bolts to the gearbox if the coupling is metal. If the coupling is rubber then it wants either a bridging wire across it and spinning with it, or the anode connection made via a brush onto the shaft after the coupling.

Pete

 

[johnlilley]

It is probably just a strip of copper bonding to connect the anode to the gland. Probably epoxied to the hull skin. Sometimes used if internal access is a bit difficult. Slightly vulnerable to damage and slightly less tidy than internal wiring but still does the same thing.

John Lilley

 

[Tranona]

Not normally necessary as stern tubes of this type are usually all bronze, although the fastenings may be stainless. However if they are bedded in sealer there is usually no galvanic action. The owner clearly has concerns about his prop and shaft, but that shaft anode is not a good idea as it it is too close to the stern tube and may restrict water flow through the cutless leading to wear. Better to connect that hull anode to the shaft internally in the normal way and remove the shaft anode.

 

[prv]

that shaft anode is not a good idea as it it is too close to the stern tube

Good point. Most engines shift forward a little as they go into gear and the prop starts pushing; this one looks like that might bring the shaft anode into contact with the bearing housing (it's not the stern gland, by the way OP, that's at the other end of the stern tube).

If this is a yacht you're considering buying (noting the signature), my non-expert opinion is that these are minor issues which shouldn't rule it out.

Pete

 

[rob2]

I can't see that the wire is doing anything useful - but no harm done either. The bearing carrier is painted over which should protect it from forming a galvanic couple anyway, although it may well be brass or bronze. The cutless bearing isolates it from the carrier so there shouldn't be a couple anyway. More important is to check that there is an internal connection through the shaft to the prop to prevent them from reacting with each other.

Rob.

 

[jerrytug]

Thanks for the answers, that's all good to know. And yes it is on my list of possibles, not going on board til the wknd though..