How do you know if your anode isn't working?

[Richard_Peevor]

How do you know if your anode isn't working?

I have a volvo saildrive anode, I've changed it a few times during the course of my boat ownership, every 2-3 years. It gradually wears but how would I know if it wasn't working? What would be damaged?

Cheers in advance,

Richard

 

[Steve Clayton]

When we bought our first boat the survey identified that all the bronze /brass(?) external fittings had de-zinctified due to non-effective anode/connectivity - all replaced.

 

[saltylegs]

On a sail drive if the anode is wearing away and the leg isn't then all is well, just check that you have continuity between the anode and the leg when you install it.
The only way to test an anode is when it is installed seperately from the items it is protecting and then you can check the continuity provided it is correctly bonded and then you can also check the current.

 

[VicS]

How do you know if your anode isn't working?

I have a volvo saildrive anode, I've changed it a few times during the course of my boat ownership, every 2-3 years. It gradually wears but how would I know if it wasn't working? What would be damaged?

Cheers in advance,

Richard

Be suspicious if the rate at which the anode corrodes away diminishes.

Be on the look out for any signs of corrosion of the sail drive leg.

When you fit a new anode be sure that there is a good electrical connection with the leg. If in doubt test it.

The standard method of testing cathodic protection is with a silver/silver chloride electrode. See http://www.galvatest.com/

 

[VicS]

When we bought our first boat the survey identified that all the bronze /brass(?) external fittings had de-zinctified due to non-effective anode/connectivity - all replaced.

Bronze does not dezincify.. it contains no zinc.
Dezincification of skin fittings indicates that they are brass.

Brass skin fittings should have a life of 5 years minimum if they comply with the relevant ISO standard.

Bronze should last almost indefinitely and dezincification resistant brass should also last well without the use of cathodic protection.