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mercathode question

outobie

Regular Contributor
Where does this piece mount?

Item 1 in the diagram

mercathode pic.jpg

I'm having some electrolysis issues with my outdrives and my boat has what I believe is an older version of this part mounted to the transom of the hull just below the water line. does part 1 mount to the transom or to the outdrive?
 
the unit mounts to the bottom of the transom housing where the hyd line hoses are.
Without the correct bonding, it wont help much. Also if there is shore power installed incorrectly or the wrong type of charger installed.
 
IMG_1679 this one.jpg

is this where you mount it? where the anode is?

I have twin engines...does that mean I should have twin mercathode devices? at present I have one that doesn't seem to be functioning

is there instruction available for how to install and ensure this is working?
 
I have an original Mercathode system from 1987 with the two little round sensors mounted on the stern of the hull.

im still getting a lot of corrosion on the anodes. I’d like to augment with a second system of the type that mounts to the bottom of the gimbal housing in place of an anode.

i understand there are 3 different versions of the system. One with a black box, blue box and orange or red box

my old system has s black box.

i boat in the upper cheasapeake bay.

boat is wetslipped in a marina

i found a good deal on s blue box system... is this ok to install or do I need to find a black box system?

thoughts?

thanks
 
I have an original Mercathode system from 1987 with the two little round sensors mounted on the stern of the hull.

im still getting a lot of corrosion on the anodes. I’d like to augment with a second system of the type that mounts to the bottom of the gimbal housing in place of an anode.

i understand there are 3 different versions of the system. One with a black box, blue box and orange or red box

my old system has s black box.

i boat in the upper cheasapeake bay.

boat is wetslipped in a marina

i found a good deal on s blue box system... is this ok to install or do I need to find a black box system?

thoughts?

thanks

If you have the original system, chances are it is causing your corrosion. Then again, unofficially these systems suck and I disconnected the ones on my boat.
 
Why yes it is��

ive got two down-on-their-luck livaboards within 50 feet, on vessels that haven’t left the dock or even had functional engines in years
 
Use of non marine electrical stuff on board plugged into the power lines causes a nightmare stray current situation for nearby boats.
 
yes, this is why I'm trying to sort out my strategy for how to deal with it.

any insight on what the best solution would be?

current question is mercathode..

1) install new and delete old
2) install new to complement old
3) install something different; what?
4) take up golf and let the elements dissolve my boat
 
Best solution...

Sink offending boats....

Kidding aside... research and see if there is a better system than mercathode would be my next step.
 
besides the mercathode the only other thing I've found is a galvanic isolator...but I'm not really sure if that does the same thing.

you seem to be negative on the mercathode system so I was hoping you had a better option in mind.
 
Why yes it is��

ive got two down-on-their-luck livaboards within 50 feet, on vessels that haven’t left the dock or even had functional engines in years

Well, you may have to move to a different marina. The merc system protects against "Some" stray voltage....Old Sh^tty boats will destroy yours even if your Mercathode system is stacked and working correctly.

Do you see any corrosion on your drive or transom assembly? Or is it all on your anodes?
 
there looks to be the beginning of some on the drives but mostly I'm just eating annodes every 2 months or so.

will a galvanic isolator help?

since my existing mercathode from 1987 (weather it's working or not) allows my annodes to last for 2 months, wouldn't it be an improvement to install a new one...maybe that will extend my annode life to 3 months?
 
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the life of the annodes seems to vary by location...the trim cylinders and the trim tabs seem to have the shortest life.

next is the one on the front top of the cavitation plate on out drives

the ones under the gimbal housing and on the prop shaft look much better.
 
will a galvanic isolator help?

Their purpose is to minimize any corrosive current that flow thru the Shorepower's Ground line (the GREEN Lead)....if shorepower isn't used, then one isn't needed.

It may be worth the investment to have one of the local marine electricians visit the boat and make some measurements - that way you will know what's going on so you can correct the issue(s) once and for all.....
 
Their purpose is to minimize any corrosive current that flow thru the Shorepower's Ground line (the GREEN Lead)....if shorepower isn't used, then one isn't needed.

It may be worth the investment to have one of the local marine electricians visit the boat and make some measurements - that way you will know what's going on so you can correct the issue(s) once and for all.....

Why yes it is��

ive got two down-on-their-luck livaboards within 50 feet, on vessels that haven’t left the dock or even had functional engines in years

This is his problem.
 
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