Go to Red Mercathode without extra anode?

Hey Guys,

I have a lot of problems of corrosion on my BIII drive. At this moment I a blue Mercathode controller and was told that I could switch to the red controller and get better protection (go from 25w to 60W??).

Do I need to change anything other than the controller? I have the gimbal mounted electrode, not transom mounted. I just want to change the controller and not put some extra anode pucket on the transom. (because of the holls I have to make)

Thanks.

Marco

I have the same issue. Let me tell you what I've concluded. I checked the Mercathode with a Merc. test probe in the beginning of the season and the readings are correct. As the season goes on and the barnacles begin to attach themselves to the gimbal mounted electrode that reading begins to decrease then disappear. If you attempt to clean the electrode there is a high risk of damaging it.
I have two non functioning puck electrodes already on my transom. I assume the previous owner switched over to the gimbal electrode when replacing the outdrive and simply left them there. What I noticed was that no matter how bad the barnacles got they never attached themselves to those pucks. Don't know why, don't care why. I purchased, on EBay, a new Mercathode setup red Controller and 2 pucks and will install them this season.
I'm all out of ideas if this does nor work work.

Hmm...good thinking.

What do you think about the pucks. Are they made from solid material? I mean...do they last very long?
If I do make a holl I only want to do it ones and good. Not that I need to replace them over a couple of years


thanks

Here is an image
the Merc part number is 42600A14


The rectangles on the pucks are made of what seems to be fairly heavy sheet metal. They are 3" in diameter. The kit includes the o-ring shown in the photo that goes between the transom and the back of the puck. I would slap on a bunch of silicone sealant in addition to the o-ring to try and keep the Atlantic Ocean out.

It is an ongoing struggle to keep these BravoIII out-drives from dissolving. They seem to last forever if you trailer or slip in fresh water with absolutely no stray electricity from your boat, your neighbors or the Marina itself. Sea Ray is moving towards using Outboards to propel these cruisers. I believe that's the way to go, dock the boat lift the drives out of the water and live to boat another day.

Just remember power consumption more than doubles when switching to Red Mercathode. So shore power is a must.

But best investment is the Probe to measure if the Mercathode is working and power is right. I check once pr. month. But I have not seen my MerCathode loose power over time - despite a lot of growth on the drive.

I have the red controller and the extra pucks. When everything is working properly, this set up pretty much eliminates corrosion. BUT.............if something fails this type of a set-up can actually create more corrosion than if you didn't have it. I'll explain this in detail based on my own personal experience. With the red controller, if one of the transom anodes fail, you actually get a lower "Hull Potential" reading (that's the reading you get when using a hull potential tester electrode, also called a corrosion tester) than you would if you had no extra anodes on the boat and corrosion really gets bad particularly at the bearing carrier under the props. I have had two of these transom anodes fail on separate occasions since my boat was new and I have had this set-up for over six years now. In one case, it resulted in my lower unit being replaced. In the second case the whole drive was replaced. So here is my advice. If you are experiencing corrosion, then by all means install the red controller and the extra transom anodes. But buy your self a Hull Potential tester (sometimes called a corrosion tester) such as this one. http://www.boatzincs.com/corrosion-reference-electrode-specs.html?gclid=CNf9-MbkuLUCFQeynQodhVwA5A Take readings at least once a month. If they are not up to the recommended reading then it's time to start troubleshooting to see what the problem is. If the readings increase after disconnecting the extra transom anodes (one at a time) then the one that changes the reading the most is likely bad and will have to be replaced.

I hate outdrives because of all the corrosion issues but the biggest aggravation for me personally is took me six years to figure out everything properly and the last thing I bought was the tester............that should have been the FIRST thing I bought but I guess you live and learn.. Luckily, Mercury replaced all my stuff under warranty but from here on out I am on my own.

Dave

Dave,

I am going to revive this old thread and change the question a bit.

I have twin Alphas with only zincs right now.

I want to maximize my protection. I am thinking of the following plan. Please advise me.

1. Install new zinc anodes in the drives including the large one under the trim cylinder manifold on the Transom Assembly. I am in saltwater a few days at a time then on a trailer nice and dry for a couple of weeks.

2. Install two separate transom-puck Mercathode systems - one individually for each drive.

I have some questions. Do I need separate systems for each drive? Is the puck system more effective than the wire on transom assembly system?