Anodes for Yamaha outboard...Zinc or Aluminum?

[crazy charlie]

2000 200hp saltwater series outboard. Has the standard zinc bar under the trim setup and skeg/fin also zinc. I have had same ones for 4 years with absolutely so deterioration at all. I clean them up on my grinding wheel upon spring commissioning.I am considering switching to aluminum anodes for added protection.Zinc bar is submerged May thru October in saltwater.Zinc skeg is only submerged while under way.Charlie

 

[Donald0039]

Zinc is proper for salt water. I would not switch.

 

[dingbat]

The only reason to switch up to aluminum is if your still having corrosion issues (better protection) or if you primarily run in brackish water.

 

[crazy charlie]

The only reason to switch up to aluminum is if your still having corrosion issues (better protection) or if you primarily run in brackish water.

No corrosion issues but I am in salt water and the zincs SHOULD have some deterioration on them.Switching to aluminum (a less noble metal)
should attract any stray current and protect my Yamaha better. Mercruiser has just about totally switched to aluminum anodes for better protection.I think
zero deterioration is not necessarily a good thing in a large marina.Charlie

 

[mike_i]

I'd stay with zinc.

 

[dingbat]

I think zero deterioration is not necessarily a good thing in a large marina.

I’d agree.

 

[mr 88]

Are you slipped at a Marina , on a hook , private dock ? Ask any fellow slippers what they use or have the same results as you ? Stray electrical current will not affect your motor while underway , so that anode is normal to show no wear . I might try to figure out a way to have both types attached to the submerged bracket, even cut one in half if need be . Trim tabs ?

 

[1960 Starflite]

I'm in fresh water. My lower units on IO and OB had really bad pitting/deterioration . The aluminum anodes showed No deterioration. I switched to magnesium anodes, now I have no deterioration on outdrives.

 

[Donald0039]

My boat is stored on a rack. No corrosion.

 

[mr 88]

I'm in fresh water. My lower units on IO and OB had really bad pitting/deterioration . The aluminum anodes showed No deterioration. I switched to magnesium anodes, now I have no deterioration on outdrives.

It's good you put the correct ones on . Maybe if you researched it awhile ago and got the correct material you wouldn't have any pitting .

 

[mr 88]

My boat is stored on a rack. No corrosion.

And that has what to do with the OPs question ? Can't wait to read someone's post about how they keep their boat on a trailer and don't have any corrosion issues .

 

[crackedglass]

I always thought the general rule was zinc for saltwater and magnesium for freshwater? I never heard of aluminum anodes on an aluminum drive?
I've been boating in both for years but I trailer my boat now but 20 years ago I kept my boat in the water on a lake in PA and there we ran magnesium anodes. Pitting wasn't the big issue though, green growth and small mussels were the bigger issue. I used to run a fuzzy loop of old 1" rope under the hull back and forth at least once a week to keep the hull clean.

 

[crazy charlie]

I always thought the general rule was zinc for saltwater and magnesium for freshwater? I never heard of aluminum anodes on an aluminum drive?
I've been boating in both for years but I trailer my boat now but 20 years ago I kept my boat in the water on a lake in PA and there we ran magnesium anodes.

YES,that used to be the general guideline and still is except in situations in marinas that have a lot of boats plugged into shore power and outdrives ,transom plates, lift cylinders all get some of the current and can deteriorate .Sometimes quickly.The zinc is supposed to take the brunt of it but in the past 20 or so years ,Mercruiser has found that aluminum anodes protect better and it is easy to tell by the condition of the anode at seasons end.On my twin Mercruiser boat I use mostly aluminum. The zinc bar on the bottom of my Yamaha outboard has not deteriorated at all in 5 years.I grind it clean and reuse it.Gonna try aluminum this year.Charlie.