Corrosion Problem....

[sailsmanship]

I am looking at buying a boat with mercruiser 5.0's and bravo III's. I think I'm being mislead.<br />The boat is a 2000 in freshwater. Both total outdrives have been replaced. He said the reason was that the previous owner had put the wrong bottom paint and didn't keep it far enough away from the drives and it had the wrong zincs on it.<br />Sounds screwy to me... Any thoughts....

 

[rodbolt]

Re: Corrosion Problem....

not to me<br /> corrosion on bravo III's can be a beyatch. even in fresh or brakish water or polluted waters they would corrode without the proper protection.<br /> some would do it in 6 months

 

[TilliamWe]

Re: Corrosion Problem....

Bravo 3 drives are touchy when it comes to corrosion. <br />I assume this is a dealer showing this boat to you? He is still giving you a "bit of a line". They probably didn't need to be replaced, but were corroded. He just "sold" the previous owner on a total replacement.<br />Send me your e-mail address, and I'll email you photos of my 1997 Bravo 3 drive that has been slipped in freshwater for the last 4 summers (it was trailered prior to that). The drive is corroded, but it doesn't need to be replaced.<br />There are two different types of annodes. The standard type and Magnesium. Magnesium is supposed to help in fresh water. But if the Mercathode system is not functioning properly, my marina warned me that the Magnesiums wouldn't last an entire summer. And they aren't cheap.

 

[Bt Doctur]

Re: Corrosion Problem....

Tip.If you do paint the bottom keep the paint at least 1 inch away from the transom housing.

 

[Don S]

Re: Corrosion Problem....

The Bravo III drives had problems and still do. With 2 large SS props, aluminum housings, and if the previous owner put copper bottom paint on the boat and had it up against the transom shield, and used the wrong anodes, YES. There could have been serious corrosion problems.<br />The service manual, ( Click Here ) has a section in it for the mercathode.<br />There are also different control boxes for the Mercathode for fresh and salt water and even the possiblilty of parallelling them together. But it all has to be checked out using the meter and tests shown in the link above.<br />If the Marina says they burn up the Magnesium anodes in less than a season, then there is probably something wrong with the wiring at that marina. BUT...... the Mag. anodes are a lot cheaper than a drive and transom shield.

 

[TilliamWe]

Re: Corrosion Problem....

"If the Marina says they burn up the Magnesium anodes in less than a season, then there is probably something wrong with the wiring at that marina."<br /><br />Don, oh no, that could never be the problem! It's all Mercruiser's fault. Actually, the guy at my marina doesn't know for sure how long they'll last, he was guessing. He was quick to say "well, you need to check your mercathode, cause nobody else is having that problem" A little CYA if I have ever heard it. <br />From what I can tell on my drive, if it keeps corroding, it will be the "bearing carrier assembly" ($261 from dougrussell.com) that needs to be replaced, not the whole drive. Of course, that's assuming I don't let the drive fill with water & stay that way for long.<br /><br />Thanks for the bottom paint info, I wondered how that fit into this problem.<br /><br />"BUT...... the Mag. anodes are a lot cheaper than a drive and transom shield."<br /><br />Yep, that is for sure.