When do you replace your anodes? Zinc or Aluminum?

Homerr · #1 March 14th, 2005, 02:41 PM

When is a good time to replace your anodes?

I don't think mine need them yet, but I was wondering when the rest of you do.

My book says 'when they are about half worn' ... problem is.. what do they mean by half?

I can't find a 'dummies guide to replacing anodes' Anyone have some pictures of going bad/very bad anodes?

And lastly, should I stick with the zinc anodes or go with aluminum?

Thanks,

H.

lenny2113 · #2 March 14th, 2005, 04:12 PM

I replace zinc anodes every season. I figure it is better to invest in zink anodes then into a new outdrive. I would say go with zink anodes. I have not used aluminum anodes as I think it makes no sence, since your drives are aluminum casting. "Sacraficial anode" serves the purpose of sacrafising itself to the electrical currant that is common to boat docking areas where shore power is almost on all boats.

I would change every season only because I keep boat in the water for the season. If you trailer your boat I would say replace it when you see zink starts falling apart.

trog100 · #3 March 14th, 2005, 04:26 PM

i think the "dummies guide would say replace em when they are half gone.. and keep the crud off em too so as they can do their job..

i also read somewhere that if u have a little aluminum boat.. all linked up shore-power wise and moored next to some big steel hulled boats for example.. your little boat becomes the sacrificial anode for the whole bunch of em.. he he

trog100

Dunaruna · #4 March 14th, 2005, 05:01 PM

A sacrificial anode can be made of any number of alloys and alloy compositions, the word 'zinc' is a commonly used generic term term for all anodes, it doesn't always mean that they are made of zinc.

Use whatever the leg manufacturer recommends, that can change depending on 'warm or cold water', 'salt or fresh' and 'alloy hull or glass'. Stainless steel props can affect your choice also.

For example, magnesium anodes are common for the type of hull I have and the area I boat in.

Half worn is a rough guide, the smaller they get, the less surface area to sacrifice. Keeping them clean also increases the sacrificial area.

Aldo.

TilliamWe · #5 March 15th, 2005, 04:21 AM

the ones that mercruiser recommends for "freshwater use only" are magnesium. Not sure what the "standard" anodes are made of.

I too have not figured out what "half gone" means, but I do know that you need to clean them off periodically so that growth doesn't decrease their ability to function.

lakelivin · #6 March 15th, 2005, 05:17 AM

Homer: out of curiosity, salt or fresh water (can't get a hint from your location "GETTIN' JIGGY WITH IT !!!"), trailored or docked, age of your boat?

trog100 · #7 March 15th, 2005, 06:16 AM

the other things of course is whatever metal u are useing as an anode it does have to be making good electrical contact with what its attached to and the boats general earthing system..

trog100

jlcjtc · #8 March 16th, 2005, 06:49 PM

bought a 1987 renken i/0 2nd hand do ya think i need to change mine?

Dunaruna · #9 March 16th, 2005, 06:58 PM

Quote:

Originally posted by jlcjtc:

bought a 1987 renken i/0 2nd hand do ya think i need to change mine?

It depends on their condition, if they are fairly new then the answer to your question would be no.

If you are not sure then the answer is yes. Better safe than sorry.

'Half worn' is just a rough guide, don't get to worried about trying to measure them so that you replace them exactly at the point when they are half worn.

Aldo