i/o corrosion bad

netting one

Petty Officer 2nd Class
Joined
Mar 23, 2010
Messages
112
I have a 1995 bravo 2 behind a chevy 350 engine. the boat is flawless and only had about 150 hrs when i got it. it never stayed in the water for more then 2 weeks and fresh water only. when i got it the outdrive was bottom painted? it now has warren off and has white corrosion all over it, pitts with white powder stuff. i have replaced all the anodes and added extras too. any ideals? i need to stop this then try to repair. thanks dan
 

Bondo

Moderator
Staff member
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Apr 17, 2002
Messages
71,130
Re: i/o corrosion bad

Ayuh,... Is it equiped with the Mercathode system,..??
If Not, it should be...
 

netting one

Petty Officer 2nd Class
Joined
Mar 23, 2010
Messages
112
Re: i/o corrosion bad

thanks for the help! im sorry i threw some rustoluim paint on it real quick to hid it like the first owner did. i do not use shore power and i believe most of the damage was done before i got it, i think i might have slowed it up. i have been reading up on it and found 2 things, one is he put a new prop on it and its like stainless but a magnet will stick to it? also i pulled the prop and in the manuel they talk about a corrosion ring( not there)! also i see on the motor there is a box called a mercathode? what is this i thought it was part of the ingntion? thanks again dan
 

Rwebber77

Petty Officer 3rd Class
Joined
Dec 31, 2009
Messages
77
Re: i/o corrosion bad

I noticed the Mercathode on my "new to me" boat and did some research. If I'm wrong someone will chime in, but from what I gathered it's a system that protects your sterndrive from galvanic corrosion. What you are seeing mounted to the engine is the controller and it sends a signal to the anode, which creates a protective field.

I also read that the Mercathode will continue to work and could drain your battery, so be aware of that if you keep your boat in the water.
 

Bob_VT

Moderator & Unofficial iBoats Historian
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May 19, 2001
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26,068
Re: i/o corrosion bad

thanks for the help! im sorry i threw some rustoluim paint on it real quick to hid it like the first owner did. i do not use shore power and i believe most of the damage was done before i got it, i think i might have slowed it up. i have been reading up on it and found 2 things, one is he put a new prop on it and its like stainless but a magnet will stick to it? also i pulled the prop and in the manuel they talk about a corrosion ring( not there)! also i see on the motor there is a box called a mercathode? what is this i thought it was part of the ingntion? thanks again dan

That will not last.

You need to strip the paint off to bare metal...... treat the bare metal with alodine then spray on some zinc chromate primer....... then your topcoat of rustoleum if you like.

The first time it is under power I bet allot of the paint will start to strip off..... you need to treat the bare metal for proper adhesion. ;)
 

Adjuster

Petty Officer 1st Class
Joined
Aug 27, 2008
Messages
233
Re: i/o corrosion bad

A grouper zinc stopped my corrosion 100% for a boat full time in saltwater. Google it or available at your local marine store. Here is a tip, make your own. Don't pay the $60.00. Do your research on galvanic corrosion. If you don't get it under control it will cost you thousands of dollars.
 

netting one

Petty Officer 2nd Class
Joined
Mar 23, 2010
Messages
112
Re: i/o corrosion bad

well guys it was a busy night working on the boat. i did find my mecathode unit under my outdrive by the tilt hoses. pulled it down and checked all my stainless cables too. went inside the boat to check out the little blue box and found no power going to the unit, it has a fuse link inside and it was bad. now how long has this been like this and why did the fuse blow? thanks again dan
 
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