Electrolysis Preventer

[abl1111]

I have a mercruiser i/o and electrolysis is wreakiing havoc on my drive, gimbal and transom bracket...

Is there a product that I can plug into an AC socket and hang into the water to somehow absorb any 'loose' electricity in my canal ? I have a problem beyond dis-similar metals - it's got to be stray electricity. And, the mercathode and sacrificial anodes are not cutting it...

I don't think a zinc grouper will do much either...
Any ideas ?

[BigLew]

Chase down the current leak!!! Don't forget the nearby boats and the docks, shorepower and dock lights if there are any present.

Also, check out "Boat Owners Mechanical & Electrical Manual" by Calder for additional information. When I worked at West Marine I used to Xerox a section for a customer who had a specific problem such as you and just give it to him. Then I told his wife to get him the book for Christmas.

Give your wife a hand with the Christmas shopping and buy a copy for her to "give" to you!!!

[McGillicuddy]

Drag a meter through the vicinity, find the likely culprit, sink his vessel (hope it's not an old Seacraft)and then give him a highlighted copy of Calder's big book ... that'll learn him Check out Chapter 5 page 211-213 in Calder's 3rd edition of Boatowners Mechanical and Electrical Manual, there he gives a 10 point plan to protect your stuff from the less concerned. Create a low resistance path to your battery and then bond everything to that good ground. You have a big challenge, you definitely will need to bond that drive shaft to a good ground. Oh, yeah, I have a nice hole saw and auger bit collection should you prefer that route. Good Luck!

[abl1111]

Thx for the insight. It is so annoying ! I take great care of my stuff and this is one of those things that's hard to deal with. I know I caught the problem very early - barely any damage at all - but I could see the start of it.

Over the years, I've kept many boats ( all outboards ) in the same slip in back of someones home. They store their i/o boat on a lift there. His neighbor has a boat on a lift in his own yard too.

So, I'm the only nearby target for electrolysis ( I'd rather share that wealth ! ). I don't know where it's coming from, but I will isolate it w/ a probe and the help of my Mercruiser mechanic.

Then, it might be tough to get a homeowner to do anything about it. Most the boats by me are outboards ( one of many great benefits of an OB ) - so their exposure to electrolysis is minimal.

I've done an enormous amount of work prepping my drive, gimbal, etc. this Spring. Sanding all the nooks and cranny's while the gimbal and transom mount are on the boat is no picnic. It actually sucked ! Then I primed with Interlux Primocon and topped w/ Interlux Trilux. I must have spent 25-30 hours sanding properly and then 3 coats of each.

If I cannot get rid of the electrolysis, or re-direct it to another target, I will have to give up my perfect slip; a private, broadside, down-the-block-from-where-I-live place.

So, if there are any ways to re-direct the electrolysis to a decoy target - I'm all ears.

[McGillicuddy]

I got my scanner working so I'll try to e-mail you a couple of pages this afternoon. Also check the possibility of a tired seal on a bilge pump, or the like, or a bad ground somewhere, which could cause an electrical leak aboard your craft (I know this is unlikely but a wise man suggested it) ... Good Luck.

[abl1111]

Mc,

Would appreciate it if you could email me any info you have.

Thx

[McGillicuddy]

Whoops check your e-mail as listed on your profile... let me know if no longer current... Mc Gill

[abl1111]

Thx Again Mc.

Holy sh*t. Everyone should read that ! Electrolysis and galvanic corrosion are insidious. It is actually scarey how stainless steel in one scenario is very rust resistant and in another, not at all; for example: if you see your SS rusting or leaving rust stains anywhere - it is loosing it's battle to corrosion - and that's above the waterline. Under the waterline - it's insane.

Question for someone who knows - I'm wondering if I throw a zinc grouper overboard and connect that to my (-) battery terminal, will that act as a sort of bonding system ( assuming all my (-) wiring is grounded to a (-)buss bar or the (-) battery ?

With regard to the below point, has anyone ever added a "brush" to ride along their drive shaft that grounds out to the (-) battery terminal ?

" you definitely will need to bond that drive shaft to a good ground. "