anodes size on Rotax (Chap/Scarab...)

[BobJohnson]

Looking to order replacement anodes before getting boat out of storage. Either to put on if needed or have on hand for future.

anyone with a Rotax boat know the size of the anodes on our boats? I know there is on on each of the cooling plates under the boat, and it appears there is one on the side of each pump. Little round guys. I know I need Magnesium for my lakes, but just want to get the right size.

if anyone has access to their boats and can either measure size or let me know if there are any item numbers / descriptions imprinted on them, that would be great... couple pics from on line showing location of anodes...

 

[JetTech72]

Rotax Anode is #461805
Dimension is 1" dia X 1/2" thick with 1/4" dia hole.

 

[BobJohnson]

Rotax Anode is #461805
Dimension is 1" dia X 1/2" thick with 1/4" dia hole.

any idea where to find these online? Been searching for a little while here and coming up empty.

 

[JetTech72]

Try # 0461805
http://www.crowleymarine.com/johnson-evinrude/parts/CODVVAI0.cfm

 

[BobJohnson]

@JetTech72 Thank you! Placing order now. That is a dangerous website. Lots of goodies. Gonna save that site for sure. Thanks again!

 

[BobJohnson]

well, almost bought these... they turned out to be Zinc anodes. I need magnesium. Search goes on. Still a great site for parts, thanks...

 

[Darrell]

What would be the reasoning between zinc or magnesium?

 

[Compatico]

What would be the reasoning between zinc or magnesium?

Magnesium anodes react at lower electrical potentials which means they will corrode faster and easier than zinc or aluminum - this is a good thing in freshwater, especially if you slip your boat in a marina where electrical potentials are typically worse causing higher rates of galvanic corrosion. Magnesium is a bad choice for saltwater because they will react and corrode very quickly which could leave your boat unprotected from corrosion if you forget to check the anodes. If you trailer your boat, or use a lift at a slip, aluminum is typically adequate. I believe BRP uses aluminum anodes for their drives so no need to change unless you slip your boat. Check your anodes once a month to see how fast they corrode and replace when half worn.