MC1 anodes

[hairchef]

I have an MC1 upper and Alpha lower what anodes do I need.

 

[ratdude747]

I assume we're talking about the trim fin that also doubles as the anode.

Anything that fits an Alpha (IIRC MC-1 is the same, as I'm pretty sure I the anode I installed on my MC1 is in fact an "Alpha" marketed unit).

Otherwise, it depends on your application. What prop? Fresh or salt water? The former determines if you need a "high-performance" Anode (extra prop clearance, what I installed when I swapped to a Piranha)... the latter determines what metal is needed. Lots of OEM and aftermarket options...

 

[hairchef]

I assume we're talking about the trim fin that also doubles as the anode.

Anything that fits an Alpha (IIRC MC-1 is the same, as I'm pretty sure I the anode I installed on my MC1 is in fact an "Alpha" marketed unit).

Otherwise, it depends on your application. What prop? Fresh or salt water? The former determines if you need a "high-performance" Anode (extra prop clearance, what I installed when I swapped to a Piranha)... the latter determines what metal is needed. Lots of OEM and aftermarket options...

I need that for sure and the 2 little knob ones on bell housing is all I see

 

[1960 Starflite]

Aluminum anodes didn't work at all for me in our sorta fresh water lake. Magnesium works very well. No more pitting on lower unit.

 

[ratdude747]

Aluminum anodes didn't work at all for me in our sorta fresh water lake. Magnesium works very well. No more pitting on lower unit.

Considering the casing is made from aluminum, no wonder. You need a metal that is more reactive than the aluminum case for it to work... or at least less-passivating than the aluminum.

Magnesium works because it is way more reactive than aluminum (anything higher on the list is the sort of thing that will fizz & go boom in water). Zinc technically isn't as reactive as aluminum, but passivation effects makes zinc work (as unlike aluminum and stainless steel, it doesn't passivate). This is why zinc is preferred for salt water... it works well enough to protect things without working so well that it burns out too fast.

 

[Scott06]

Aluminum anodes didn't work at all for me in our sorta fresh water lake. Magnesium works very well. No more pitting on lower unit.

What prop are you running. I had zero issues with aluminum annodes in fresh when I ran aluminum props. went to a big 4 blade revolution 4 and had some pitting like u mention. This is lift kept not in a marina not connected to shore power.

also found better results with oem merc magnesium vs the magnesium i got from boatzincs. much less corrosion with oem ones and they erode more .

 

[1960 Starflite]

What prop are you running. I had zero issues with aluminum annodes in fresh when I ran aluminum props. went to a big 4 blade revolution 4 and had some pitting like u mention. This is lift kept not in a marina not connected to shore power.

also found better results with oem merc magnesium vs the magnesium i got from boatzincs. much less corrosion with oem ones and they erode more .

3 blade aluminum on pontoon and 4 blade on Mercruiser. Boats sit in water May to October, no electric at mine or surrounding docks. Our lake is run-off feed. I considered it a 7 mile long pond.