Logo
Results 1 to 20 of 20
  1. #1
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default mercathode question

    Where does this piece mount?

    Item 1 in the diagram

    Click image for larger version. 

Name:	mercathode pic.jpg 
Views:	13 
Size:	45.9 KB 
ID:	16523

    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?

  2. #2
    Join Date
    Jun 2006
    Location
    Spotswood, NJ, USA
    Posts
    3,841

    Default Re: mercathode question

    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.

  3. #3
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    Click image for larger version. 

Name:	IMG_1679 this one.jpg 
Views:	14 
Size:	51.0 KB 
ID:	16527

    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?

  4. #4
    Join Date
    Jun 2006
    Location
    Spotswood, NJ, USA
    Posts
    3,841

    Default Re: mercathode question

    Yes, you remove that anode and install the mercathode one.http://www.boatfix.com/merc/Techbk/94/94hs7.pdf
    Last edited by Bt Doctur; 09-23-2017 at 05:10 AM.

  5. #5
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    Thanks

  6. #6
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    Is this the original mercathode from 1987?

    cant seem to add pics...
    Last edited by outobie; 10-27-2017 at 12:00 PM.

  7. #7
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    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

  8. #8
    Join Date
    Sep 2010
    Location
    Jersey Shore
    Posts
    4,597

    Default Re: mercathode question

    Quote Originally Posted by outobie View Post
    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.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Mercruiser/Mercury Certified
    Let the insanity begin.

  9. #9
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    So what’s the solution?
    disconnect the existing and install? A new mercathode? Something else?

  10. #10
    Join Date
    Sep 2010
    Location
    Jersey Shore
    Posts
    4,597

    Default Re: mercathode question

    Quote Originally Posted by outobie View Post
    So what’s the solution?
    disconnect the existing and install? A new mercathode? Something else?
    Where do you slip your boat? Is it parked in a marina next to an old POS that is not taken care of?
    Chris
    Dockside Marine Services
    Jersey Shore.
    Mercruiser/Mercury Certified
    Let the insanity begin.

  11. #11
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    Why yes it is��

    ive got two down-on-their-luck livaboards within 50 feet, on vessels that havenít left the dock or even had functional engines in years

  12. #12
    Join Date
    Jun 2008
    Location
    Island Heights, NJ,
    Posts
    2,600

    Default Re: mercathode question

    Use of non marine electrical stuff on board plugged into the power lines causes a nightmare stray current situation for nearby boats.
    Capt Bob
    1969 23ft ChrisCraft Lancer
    Merc 5.7L 260HP/ Volvo 280
    1972 22ft Bristol
    Honda 7.5HP 4 stroke Long shaft

  13. #13
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    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

  14. #14
    Join Date
    Jun 2008
    Location
    Island Heights, NJ,
    Posts
    2,600

    Default Re: mercathode question

    Best solution...

    Sink offending boats....

    Kidding aside... research and see if there is a better system than mercathode would be my next step.
    Capt Bob
    1969 23ft ChrisCraft Lancer
    Merc 5.7L 260HP/ Volvo 280
    1972 22ft Bristol
    Honda 7.5HP 4 stroke Long shaft

  15. #15
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    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.

  16. #16
    Join Date
    Sep 2010
    Location
    Jersey Shore
    Posts
    4,597

    Default Re: mercathode question

    Quote Originally Posted by outobie View Post
    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?
    Chris
    Dockside Marine Services
    Jersey Shore.
    Mercruiser/Mercury Certified
    Let the insanity begin.

  17. #17
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    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?
    Last edited by outobie; 11-15-2017 at 05:11 PM.

  18. #18
    Join Date
    Jun 2017
    Location
    Annapolis, MD
    Posts
    84

    Default Re: mercathode question

    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.

  19. #19
    Join Date
    Sep 2008
    Location
    Maryland - USA
    Posts
    6,803

    Default Re: mercathode question

    Quote Originally Posted by outobie View Post
    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.....

  20. #20
    Join Date
    Sep 2010
    Location
    Jersey Shore
    Posts
    4,597

    Default Re: mercathode question

    Quote Originally Posted by makomark View Post
    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.....
    Quote Originally Posted by outobie View Post
    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.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Mercruiser/Mercury Certified
    Let the insanity begin.

Similar Threads

  1. Mercathode
    By tuna_man in forum Mercruiser Sterndrive Forum
    Replies: 5
    Last Post: 03-13-2015, 11:57 AM
  2. MERCATHODE Questions
    By abl1111 in forum Mercruiser Sterndrive Forum
    Replies: 11
    Last Post: 05-02-2014, 06:16 PM
  3. Mercathode Question for Corrosion Experts
    By 30 Commander in forum Mercruiser Sterndrive Forum
    Replies: 0
    Last Post: 08-02-2011, 12:10 AM
  4. MERCATHODE INSTALL QUESTION ON 30
    By gizmolvr in forum Mercruiser Sterndrive Forum
    Replies: 2
    Last Post: 03-26-2010, 02:12 PM
  5. MERCATHODE
    By bobkoss in forum Mercruiser Sterndrive Archive
    Replies: 10
    Last Post: 02-25-2008, 03:49 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •