corrosion

Corral42

My new to me 370 has a serious outdrive corrosion issue. I replaced the bravo 3X lowers 2 months ago and when I had the boat pulled yesterday to replace the uppers due to fluid leaks. I can see that it's already attacking the new lowers. I can rule out the shore power cord and pedastal because my 320 was there for 10 years within issue. The anodes are working but not well enough. Any ideas where to start?

LaRea

If you're in fresh water, are you using magnesium anodes?  Maybe your Mercathode system is not working.  Check the two circuit breakers labeled "Cathode" on the battery switch panel near the transom door.  

PickleRick

Could also be caused by surrounding boat or boats with a stray current, got any new slip neighbors or any repairs done to the electric system on the docks?

Corral42

LaRea said:

If you're in fresh water, are you using magnesium anodes?  Maybe your Mercathode system is not working.  Check the two circuit breakers labeled "Cathode" on the battery switch panel near the transom door.  

Aluminum brackish

GMSLITHO

I installed a galvanic isolator on my 270 2 years ago that seemed to solve the problem 

Liberty44140

Just because there was not an electrolysis issue before does not mean there isn’t one now. Could be a new boat close by, change in shore power or your boat. Our marina uses a clamp amp meter on all of our shore power cords to see power loss. 

raybo3

Could be anything. Loose wire in your shore power. Power cord could be breaking down. Loose neutral or ground either on your boat or in the shore power panel can cause major problems.  

Corral42

GMSLITHO said:

I installed a galvanic isolator on my 270 2 years ago that seemed to solve the problem 

I am going to go this route

Cableguy Greg

Corral42 said:

GMSLITHO said:

I installed a galvanic isolator on my 270 2 years ago that seemed to solve the problem 

I am going to go this route

There is already one installed. 

GMSLITHO

i don't think the factory installed one .my 270 didn't have one 

Aqua_Aura

On Facebook @Alswagg had mentioned there is one installed but it is inline and behind the panel I think. It is not a typical one you would buy at the store but he said there is one 🤷🏽‍♂️

Ian

Not sure I’ve seen one in my 2003 FV310. I’ve had that panel open a few times.

YYZRC

My 330 had one - behind the panel. 

Just checked my 350 and can’t find one!

Aqua_Aura

Does anyone have a picture of what these factory ones look like? 

Corral42

I found the problem. The ground was not tightened properly. Completely loose connection. I replaced it with the failsafe.

GMSLITHO

funny they have the torque specs right on it 

Aqua_Aura

@Corral42 where was it located? 

Corral42

Aqua_Aura said:

@Corral42 where was it located? 

Behind the electrical panel

Aqua_Aura

I ordered the promariner galvanic isolator as I am also dealing with a corrosion issue now. After pulling the boat the drive is showing signs of corrosion and the anodes we're still 90 percent. After reading online I am going to check for resistance between the anode and outdrive, may need to clean up the contact points. I have checked for stray current and don't see any also if there was I think the drive would be much worse after 3 years in the water. 

aero3113

This is the first time the boats out of the water in three years?

Aqua_Aura

Yep. Definitely should have done it sooner but sometime life doesn't cooperate. Bottom came clean and no blistering. 

aero3113

@Aqua_Aura , It’s nice to know that you had no reason to pull it out in the three years 👍🏻👍🏻.

Aqua_Aura

Yes I was worried about the fiberglass below the water and I know everyone says the newer resin is fine and it actually was 😃. I would have liked to have seen the outdrive sooner though, I'll get it cleaned and paint it before the fall and check on it more often. The boat lift is extremely convenient and it belongs to the club so I can pull it anytime I want. 

aero3113

That’s awesome that you have access to the lift!!

J3ff

Wow and folks from the North thought I was crazy for leaving it in for 13 months in salt without pulling it!! It's about to hit 11 months and it has ZERO growth on the paint and I've only had to scrape the drive once!

raybo3

@J3ff what about the zincs? I pull my boat in August to have it rezinced. 

J3ff

I do that in the water  at the sandbar @raybo3

Aqua_Aura

I got my galvanic isolator yesterday 😃. That's probably the easiest thing I'll install other than having to be twisted up in the aft corner trying to mount it.