My Bravo 3 corrosion problems appear to be resolved

D

Dave S

Well-Known Member
TECHNICAL Contributor
Oct 3, 2006
6,014
Upstate South Carolina
Boat Info
Boatless
Engines
Boatless
A little bit of background first. Our lake is especially hard on Bravo 3 units and it is not uncommon to see B3s with a lot of corrosion on them after only of few months in the water. When my boat was brand new I bit the bullet and installed extra anodes on the transom and later updated to the heavy duty mercathode. That protected the upper part of the outdrive just fine and I never got any corrosion on the upper unit or the transom plate. But the lower unit would always corrode around the prop hub, the skeg, and the bearing carrier. That corrosion, particularly around the bearing carrier, got so bad that Mercury decided to replace my lower unit under warranty seven months ago. So yesterday I had the boat taken out of the water after being wet slipped that whole seven months. To my pleasant surprise there was no signs of corrosion whatsoever on the outdrive as you can see in this picture.

DSC08013.jpg


At the same time they replaced the lower unit, they also replaced the Mercathode on the transom plate.

DSC08021.jpg


I am convinced this was one of the main culprits that has plagued me and may have not been working properly since I got the boat. There is another posting on our board about replacing this unit every few years and you may want to look at that post also. http://clubsearay.com/forum/showthread.php?t=29491&highlight=paper

You can bet your bottom dollar that the transom mercathode unit will get replaced every few years from here on out on my boat.

Dave
 
Last edited:
That's good to see Dave. Those newer generation BIIIs seem to be doing much better.
 
By the way if you look closely you will see a boat next to mine and you can see his B3. That drive is trashed and it's a wonder it even works it has so much corrosion on it.
 
Merc is replacing my ODs after 1 season.
Im also going to add zincs to my trim tabs.
See my post on BIII corrision.
 
Glad all is going well for you. You neighbor in the photo below may be running out of luck.

DSC08013.jpg


Looks like an older 240 or 260 next to you. Mmmmm.....No bottom paint and the drive looks like it will need a money injection soon.
 
Dave S said:
By the way if you look closely you will see a boat next to mine and you can see his B3. That drive is trashed and it's a wonder it even works it has so much corrosion on it.
Click to expand...

Missed your comment.

Dave you do realize these same guys are the ones who can get decades from a drive that appears as though it should died a long time ago.
 
Last edited:
dave; did your old drive have the anode attached to the rear prop shaft?
the b-3 i bought last year for the 230 does, but the ones on the 310 we just got dosnt. i'v been tying to decide whether or not to drill shaft and tap so as to install anodes over the prop nut.

also installed new merc cathode last summer on 230 but wasn't aware of a heavy duty unit. it looks like the one in you pict.
is there a way to tell one fro the other?
 
Last edited:
Dave S said:
So yesterday I had the boat taken out of the water after being wet slipped that whole seven months.
Click to expand...


Are you serious that that picture was taken after it was pulled after seven months? Did you wash the boat first?! You must have one super clean lake...my boat would look worse than that after being in the water for 2 hours!
 
garryowen said:
dave; did your old drive have the anode attached to the rear prop shaft?
the b-3 i bought last year for the 230 does, but the ones on the 310 we just got dosnt. i'v been tying to decide whether or not to drill shaft and tap so as to install anodes over the prop nut.

also installed new merc cathode last summer on 230 but wasn't aware of a heavy duty unit. it looks like the one in you pict.
is there a way to tell one fro the other?
Click to expand...


good god NO man!!...........they make a simple bolt on anode for out years B3's....

edit: in the post above is the right one.They are about $20 more than the standard but you only need to buy the special bolt/nut assembly once.The anode is actually the same on both styles.
 
Presentation said:
Please do not try to drill a hole in the shaft.

The shaft is hardened steel.
Instead go with this product…..
Oh, just doing full disclosure, they are a site sponsor.

http://www.boatzincs.com/MERProp-Nut-D-mag.html


propeller-nut-mag-complete.jpg
Click to expand...


thank you very much; will get 2 coming for smiles to go, our 310.

had the marina haul and redo all the rubber parts in the drives and new lower shift cables, gimbal bearings and trim limit and gauge senders when we got the boat.

mentioned to them the lack of prop anode and they didn't think it was near as big a deal as i did
 
Presentation said:
Glad it hear its going well Dave.

Any chance you have a zoomed in photo of the power trim anode?
Click to expand...

Are you speaking of the anode on the end of each trim cylinder? If so, the answer is no.



SeaRide said:
Missed your comment.

Dave you do realize these same guys are the ones who can get decades from a drive that appears as though it should died a long time ago.
Click to expand...

Charlie.........you are probably right. If you never clean up the corrosion you don't take off any good metal in the process as well so maybe it makes sense. But on that B3 the Skeg was corroded so badly that the edges were actually scalloped on the bottom. :wow: The boat is an older 245.

Gunn said:
Are you serious that that picture was taken after it was pulled after seven months? Did you wash the boat first?! You must have one super clean lake...my boat would look worse than that after being in the water for 2 hours!
Click to expand...

I didn't wash once it was out of the water. That is typically how they look comming out of our lake as long as the boat is used on a regular basis (we use ours every week even during the winter). And during the winter growth is not much of a problem anyway. In the summertime they may have more growth on them because of the warm water but not much more.
 
Dave S said:
By the way if you look closely you will see a boat next to mine and you can see his B3. That drive is trashed and it's a wonder it even works it has so much corrosion on it.
Click to expand...

if my out drive looked like that, i wouldn't even be able to live with myself.....:smt009
 
Presentation said:
The trim cylinder anode looks funny but when I try to zoom in the picture is all blurred. It may be nothing.
Click to expand...

Looking for more problems for me too deal with? :smt043

I think what you are seeing is the normal u-shape of the anode itself that allows you to slip it over the cylinder ram. The opening is oriented towards the bottom of the ram and maybe some darker coloration in the indentations where your wrench goes to attach the bolts on either side may also make the anode look a bit strange in the picture.

The anodes are all in good shape because that is another thing I looked at closely too. It will probably be another six months before those anodes need replacing.
 
You must log in or register to reply here.

Forum statistics

Threads
113,224
Messages
1,428,905
Members
61,116
Latest member
Gardnersf
Back
Top