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Electrical questions

"Now that my boat is up and ou

"Now that my boat is up and out of the water, the omc drives don't look so hot. Seem to have a lot of corrosion. The sacrificial anodes don't seem to be so badly eroded. I am wondering if this is electrical problem or the anodes of the wrong alloy ? If so were do I start to look ? what tests or checks are involved ? Every year I go through the same ritual of sanding down the rust and repainting the drives.Is there some special paint that I can use that will last more than one season with out the paint backing process? Thanks in advance for sharing your knowledge"
 
"Unless you test your boat&#39

"Unless you test your boat's galvanic action with a meter, you don't know if you have the right anodes, or if they are working. Being an aluminum boat owner, I have a rig and test it regularly.

Here's my advice to you:

1. Remove the anodes, clean where they attach thoroughly, and install new ones. Treat the connection as an electrical connection, for that's what it is.

2. Check with a meter to see if all the exposed metal parts on your boat are grounded together, with jumpers. Any part not connected will cause problems.

3. IF you are in fresh water ONLY, try using magnesium anodes.

4. If all else fails, buy or make yourself a magnesium 'guppy' and hang it over the side while docked.

Jeff"
 
"Jeff, I may be misinterpretin

"Jeff, I may be misinterpreting what you mean on #2. Everything I've ever read says not to bond the external parts of the boat together as it creates paths of electricity to flow. Nigel Calder recommends, I believe, one good ground to the outside of the boat & everything else grounded to it. Do you feel differently? I'm interested as I too need to test my galvanic condition in my new slip, but I'm not sure how to go about it."
 
"Hi Jeff...Thanks for your qui

"Hi Jeff...Thanks for your quick response and down to the point. YOU mentioned to use a meter to check the galvanic action. What kind of meter is it, and where do you get it? After doing all you have suggested and making the magnesium 'guppy' where does it connect to, Shore power or boat ground? Thanks in advance."
 
You can use any ohm meter to c

You can use any ohm meter to check and see if you have a resistance reading as close to zero as you can get (which is probably not going to happen as there will be some resistance in the grounding wires and connections). You can pick up cheap digital voltmeters for under $10.

If there is any galvanic action it might affect the resistance readings you are looking for.
 
"Hi Mark.. MY outdrives a whil

"Hi Mark.. MY outdrives a while ago were painted by the marina mechanic and they lasted one season, after that I started doing it my self. I am using metal primer and paint. Since I was told that the only way to hold for long time, I have to send them out to a specialty shop were they sand blast them and bake the paint at a cost of $2ooo a piece."
 
Hi Joe thanks for your input.

Hi Joe thanks for your input. Can you fill me in little bit more regarding galvanic action how it works. Since I have no clue how it works?
 
"Lots of questions...

You c

"Lots of questions...

You can build your own galvanic meter with a probe, a cheap VOM (Harbor Freight--4 bucks), a clamp and some wiring. The photo shows what mine looks like. Here's URLs for the probe:

http://www.farwst.com/fwst/refelect/gmc09.htm

or,

http://www.boatzincs.com/corrosion-reference-electrode.html

A source for magnesium to build a guppie:

http://www.engineeringshopper.com/index.cfm/fuseaction/shop_prodListForCat/mktID/1/catID/1/

You want all of the NEGATIVE 12 volt DC metal items all tied together on your boat. It doesn't really matter how it's done, but they need to be electrically connected. Then you add the right type/ amount of anodes to potect theworks (and check it now and then with your meter).

221243.jpg
"
 
Thanks ones again Jeff for all

Thanks ones again Jeff for all the effort you putting into this. Still more questions to come your way. What tests can I do while my boat is out of the water? By the way I checked "boat zinc .com " and their probe is connected to the - on the meter and their + to the DC ground bonding system. Are this tests done with boat batteries connected?
 
"..."What tests can I do w

"..."What tests can I do while my boat is out of the water?"

None. Sorry.

...."By the way I checked "boat zinc .com " and their probe is connected to the - on the meter and their + to the DC ground bonding system."

That's backasswards, but it might still work--you're just measuring voltage.

..."Are this tests done with boat batteries connected?"

Should not matter, but if it does, something is dead wrong!

Jeff"
 
"Thanks Jeff for excepting my

"Thanks Jeff for excepting my bombardment of questions, It's,so hard to get an honest answer from professionals that do it for living. without the sing along. Keep up the good works..."
 
West Marine sells the silver/s

West Marine sells the silver/silver chloride element for about half the price.
 
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