anode

[Sailwood]

Is there a need/place for a pencil anode in the A4? Found a depleted one, when boat was purchased, in the tool box.

Doug

[Don Moyer]

Doug,

The only place where you would find a zinc anode in the Atomic 4 would be on the heat exchanger (assuming you had fresh water cooling). You can see these anodes (http://www.moyermarine.com/cgi-bin/shopper.cgi?preadd=action&key=CFWK_04_268) in our online catalog.

Regards,

Don

[pv140]

Do you mean that anodes are not needed on the prop shaft or anywhere else? Also, are anodes needed if your boat is kept in fresh water?
Fred

[Don Moyer]

Fred,

I need to tell you up front that I am not an authorative source for cathodic protection information, so I hope others will weigh in on this subject. Cathodic protection is a very specialized field, and simple though the galvanic cell part of the process is, when you apply the science to specific issues on a boat, it apparently becomes confusing because debates still rage among the experts with respect to everything from lightning protection issues to whether or not major items on a boat should be isolated or bonded together and grounded for best cathodic protection.

In terms of using zincs on the Atomic 4, I rely on Universal's position, which was that the Atomic 4 castings were made from a corrosive resistant alloy and that zincs were unnecessary. We have heard of several customers installing small pencil zincs through the water jacket side plate but to this point we have no credible evidence that these zincs have any measurable positive effect on the corrosion process.

The manufacturer of our heat exchangers does provide a pencil zinc to use in their exchanger, so we naturally recommend that you check and replace this zinc as necessary, simply because the manufacturer recommends it.

For issues outside of the engine compartment (and for whatever it's worth), I have always installed a zinc on the prop shaft of each of our boats, and on the strut of our Catalina 30, simply because if I didn't do so, these things would tend to show signs of corrosion.

Rightly or wrongly, I have also always used a flexible prop shaft coupling on all three of our sail boats, mostly as a vibration dampening expedient. While I realize that the flexible couplings also isolated my engine from the prop shaft, I have no idea whether or not this had any beneficial effect on preventing engine corrosion. I have never had any evidence of corrosion on any of our engines, but I suspect that this is mostly because I have always installed fresh water cooling.

Don