Bravo 3 Corrosion issue.

[rick3452]

When I purchased boat in October the out drive looked to be in very good shape. Last week I had the boat pulled for 100 hr service and the change was huge. Its a 2000 5.0 MC with a Bravo 3. It does have the Mercathode system on it. I called a Mercruiser suplier today and he assures me that the new lower units $2,900 are much improved. Has anyone had expierience with the later units?

Thanks as always.........Rick

Boat is 24/7 in Brackish water with active 4 foot tides

 

[Mischief Managed]

Re: Bravo 3 Corrosion issue.

New lower unit is not going to fix the root cause. You may have the wrong anodes, worn out anodes, a faulty Mercathode, or stray current issues near the dock. Address the root cause first, and then change the lower, if you need to. If it's not leaking oil out or water in, I'd clean it up, paint it properly and keep using it.

 

[Don S]

Re: Bravo 3 Corrosion issue.

They changed the alloy of the aluminum. But you really do need to verify you are using the proper OEM anodes.
Here is a 2002 service bulletin from Mercruiser on how to check your system.
http://www.4shared.com/document/ViLRp-nH/02-06_Corrosion_Prevention_and.html

 

[HT32BSX115]

Re: Bravo 3 Corrosion issue.

New lower unit is not going to fix the root cause. You may have the wrong anodes, worn out anodes, a faulty Mercathode, or stray current issues near the dock. Address the root cause first, and then change the lower, if you need to. If it's not leaking oil out or water in, I'd clean it up, paint it properly and keep using it.

There's so much other stuff going on in marinas, variations in salinity, stray currents, anode problems, electronic anode problems,.......... if at all possible, I'd trailer the boat.

I know that's not always possible,

There is a process to set up an electronic anode.

If it's not done correctly, and/or if "things" change (stray currents and salinity) over time and the electronic anode is not checked regularly, It can actually INCREASE galvanic corrosion.


Good luck.....

 

[Bondo]

Re: Bravo 3 Corrosion issue.

New lower unit is not going to fix the root cause. You may have the wrong anodes, worn out anodes, a faulty Mercathode, or stray current issues near the dock. Address the root cause first, and then change the lower, if you need to. If it's not leaking oil out or water in, I'd clean it up, paint it properly and keep using it.

Ayuh,... I agree with MM,... Somethings Wrong,...
You can pretty much See where it was reacting with the SSteel props...
Fix the Problem,...
Then clean up that bit of corrosion, 'n give it a good shot of Rustoleum...
That housing looks servicable in the pictures...

I've never had the problem, though I heard of Hot marinas, 'n how Bad livin' in the Brine is...

 

[rick3452]

Re: Bravo 3 Corrosion issue.

Many thanks everyone, I will reserch problem before replacing.....

 

[TilliamWe]

Re: Bravo 3 Corrosion issue.

At this point, all you need is a new rear bearing carrier and seal. The housing is fine. But as the others have said, you need to fix the underlying problem. I am guessing you are keeping the boat in salt water?


This rear bearing carrier was still okay. Notice how much worse (you seal is really exposed) yours is.

This case was still fine, and yours isn't this bad really.