Leaving boat plugged into shore power/corrosion concern.

[daileyinterest]

First let me say I purchased a used 310 dancer with 350mags/bravo111 drives and just had the drives repaired and repainted from corrosion. Now the question, I currently do not have the boat plugged into shore power and I have all the switches turned off, including the battery switches. Thinking that would help prevent corrosion. Now Iam finding out that the MerCathode system (if it even has one and what ever that is) operates on 12v, if I have everything turned off I wondering if Iam creating more harm then good. But on the otherhand the galvanic isolator (what ever that is) is only needed when I have the shore power plugged in. What should I be doing properly to minimize corrosion and enjoy all the boat has to offer.

Help, Iam so confussed! :smt017 Thanks!

 

[Dave S]

I recommend you read thru this thread first. http://www.byowneryachts.com/forums/phpBB2/viewtopic.php?t=926&highlight=mercathode

You really should leave your boat plugged into shore power to keep your batteries charged up. But you should also consider some additional protection for your B3s if that has been an issue in the past. I think the above thread will cover both of those things pretty thoroughly.

 

[JC3]

DaveS is right on. JC

 

[estebanj]

With B3 drives, the ideal situation is a lift. Is this an option for your slip?

Like Dave said, if it must stay in the water, leave shore power on. Make sure the mercathode and galvanic isolator are working properly. Also, inspect your anodes regularly. And consider adding the transom mounted mercathode system to suplement the drive mounted one (2 transom pucks with a higher power red controller).

Esteban

 

[comsnark]

More importantly: Will the bilge pumps work if the batteries are off?

I leave my shore power hooked up simply to ENSURE that the bilge pump (if something stupid happen) doesn't go dead because of a dead battery.

Of course. . .on my 30 year old sailboat, I don't even have an automatic bilge pump. . . and I get lots of water intrusion due to bad deck fittings (I suppose I should fix that one of these days).

 

[Cap10Pat]

The mercathode system and the bilge pumps should be wired directly to the battery, and not subject to the battery switch. So you should be okay.

Personally, I don't leave my boat plugged in unless I have a reason to, but I'm definitely in the minority on that.

The biggest thing you can do is make sure you have good anodes - made of real zinc if you are in salt water. Make sure you have the new anode that goes in the center of the propeller. Then check your zincs during the year. I've seen a couple of damaged B3s this year, and every one of them had their zincs electrolized away. So they were protected through about August. You may have to install new zincs before the summer is over. But that should protect your drives.

 

[estebanj]

The recommended anodes for salt water are made of aluminum.

This is from BoatZincs.com:

Zinc anodes are suitable for pre-2001 Mercruiser outdrives that operate in salt or brackish water, replacing deteriorated original zinc anodes.

Aluminum anodes are more active than zinc anodes and suitable for Mercruiser outdrives that operate in salt, brackish or fresh water. Since 2001, all Mercruiser outdrives with stainless steel propellers were delivered with aluminum anodes.

Magnesium anodes are highly active and suitable for Mercruiser outdrives with stainless steel propellers that operate in fresh water only.

Esteban

 

[daileyinterest]

Thanks everyone for your replys. Now does anybody have a good recommendations on how to get rid of my headache!

Just to play it safe for now I plugged the boat in. Even if the system is direct wired to the batteries they will stay fully charged.