Salt Water Corrosion, Time to bust out big BOAT dollars...

ZZ13 said:
Great explanation. Thanks. I can see in the finished picture in your thread where the bottom of the pin is. Does the fact you have a little stainless steel piece there (the bottom side of the pin) add any further concern about more dissimilar metals underwater? My whole reason for these questions was to hone in on whether anything preventative could be done to either eliminate or lengthen the time for failure in salt water. The SS pin looks like the only option. I guess there probably isn't room to custom make/bond a "cover" over the underside of the pin to completely seal it off from the water.

Thanks again for the explanation.
Click to expand...

I'm not worried about the extra stainless, not as much surface area as a drive shower, the BIII has a lot of anode area and if the mercathode is working there shouldn't be any issues. Kind of a toss up between the corrosion that is already going to happen anyhow or at least not wrecking the seal.

There is more of the pin exposed than the bottom, where it goes through the gimbal ring is a square hole that is overcut on the corners and that whole area was packed with salt. Plus there is the area under the seal that is exposed and thats where the real problem is.
 
fwebster said:
A man only wants to experience the "Mercruiser Corrosion Perfect Storm" that simultaneously gets cooling, exhaust and outdrive parts once in his lifetime..............I'd be considering alternatives to this boating thing that don't involve outdrives.
Click to expand...

And here is where I'm confused about the advantages of pod drives. Why wouldn't they eventually suffer the same kind of failures with all those mechanics permanently submerged?

(sorry for the highjack)
 
I have owned both the Bravo 3 on my 240 and currently Alpha II drives on my 280. I had to replace the steering pin and seal on the Bravo 3 and the corrosion on the drive was unstoppable even with a mercathode and new anodes every 6 months . The Alpha sitting at the same dock space without the mercathode for the last 2 years in salt water (full time) has no corrosion at all. It seems to me the Bravo 3 has a design flaw beyond the normal high maintenance of owning an stern drive boat

BTW the Bravo 3 is a better preforming drive -but can't complain about the Alpha
 
copb8tx said:
And here is where I'm confused about the advantages of pod drives. Why wouldn't they eventually suffer the same kind of failures with all those mechanics permanently submerged?

(sorry for the highjack)
Click to expand...



I think the Zeus pod is bronze, plus the assembly that mounts to the floor of the boat to which the pod is bolted is fully gasketed, unlike outdrives that rely on a series of separate o-rings, bellows, and seals to keep various components dry. Don't get me wrong......I don't want either on a boat I own, just offering a reason/opinion.
 
kkalsch said:
I have owned both the Bravo 3 on my 240 and currently Alpha II drives on my 280. I had to replace the steering pin and seal on the Bravo 3 and the corrosion on the drive was unstoppable even with a mercathode and new anodes every 6 months . The Alpha sitting at the same dock space without the mercathode for the last 2 years in salt water (full time) has no corrosion at all. It seems to me the Bravo 3 has a design flaw beyond the normal high maintenance of owning an stern drive boat

BTW the Bravo 3 is a better preforming drive -but can't complain about the Alpha
Click to expand...

The 280DA's at our Marina with Alpha drives don't have any corrosion either but all the B3s do (including mine). The big difference is the fact they have aluminum props too. Without the mixture of stainless and aluminum there are very few corrosion problems caused by electrolysis.
 
Dave S said:
The 280DA's at our Marina with Alpha drives don't have any corrosion either but all the B3s do (including mine). The big difference is the fact they have aluminum props too. Without the mixture of stainless and aluminum there are very few corrosion problems caused by electrolysis.
Click to expand...
The Sea Ray shop around here is pushing painting the stainless steel Bravo III props. Its $250 a drive to paint the props and $250 a drive to paint the drives if they do it. To be done annually. So for a twin engine boat that's $1 full Boat Dollar per year for drive painting. Anyone know if painting the props is a big help, little help, or no help at all? Also, do the props have to be SS? Isn't there a material equally as strong/inflexible that could be used for the props that is electrolysis inert? Looks like a business opportunity...
 
Dave S said:
The 280DA's at our Marina with Alpha drives don't have any corrosion either but all the B3s do (including mine). The big difference is the fact they have aluminum props too. Without the mixture of stainless and aluminum there are very few corrosion problems caused by electrolysis.
Click to expand...

I have stainless props -but only one prop per drive vs two. Maybe the second prop makes the difference ?


 
Last edited:
Merc added the prop anode and an extra anode on the cavitation plate in 2004 on the bravo IIIs. Didnt save my original drive though. Even the new drive replaced late 2010 (and never seen salt water) is showing some pitting/erosion on the seal retainer under the props.

Having the proper anodes for the type of water you are and keeping them clean, plus a working mercathode is a must in saltwater. If you are in a slip next to another boat(s)with grounding issues it doesnt matter what you do.. Volvo Pentas corrode away as well in salt water, thats why they came up with the composite drives, but they had their own issues.

Either way I dont think the swivel pin will be saved by anodes, its steel and its actually rusting just like any pice of steel left in the water. My boat was kept on a lift when it was in salt water, that may have made it worse then just leaving in the water as far as rusting the pin goes. Same with the inlet hose corroding shut, even though the hose itself kind of seals it once the paint is compromised and the bare aluminum gets saturated with the salt that cant easily drain or be rinsed off its going to start corroding. Good chance that hole where the water intake hose goes into isnt painted or its thin and it gets rubbed off when the hose is installed.

Its pretty easy to spot the rusty swivel pin and water leaking in, but the water intake hose getting corroded shut is an issue as well. Mine was corroded about 1/2 closed and my water pressure was always a little low at higher RPM, after the repair the water pressure nearly doubled at 3500rpm. I never had any water temp issues but if the cooling was marginal due to some other problems like a worn impeller housing that closed off hose would cause all kinds of headaches I bet.
 
kkalsch said:
I have stainless props -but only one prop per drive vs two. Maybe the second prop makes the difference ?
Click to expand...

It may very well be the two props that pushes it over the edge. I know of a twin engine Bayliner in our Marina that has a Bravo 1 or 2 drive and he only has one stainless prop and has very little corrosion issues. On mine the additional anode pucks on the transom together with the heavy duty Mercathode controller help immensely with corrosion. But twice now one of the anodes has failed and by the time I caught it the tin worm had struck big time. Complaining to Mercury got me a new lower unit the first time and just last year when it happened again, they replaced the whole drive.
 
Would this be covered under Merc's warranty?
 
So all the work is done. I'll be sea trialing it next week. One additional item that came up involved the transom. When they removed the transom assembly, the transom was warped. See photo. They did glass work and gel-coat work to put it all back into alignment. Have others seen this happen or could this have been like this originally?

Thanks,

WILKEY 501575.2000.1 020.jpg
 
Everything checked out great. Had to tighten up some hose clamps after running it a bit, but so far all is well.

New assembly in comes with more than I expected...note there is now external access to steering pin nut....
uploadfromtaptalk1360812116499.jpg

Nice to have a clean and dry bilge again...
uploadfromtaptalk1360811926778.jpg


Had some new carpets done up as well. Ordered them from snapincarpets.com with upgraded backing.
uploadfromtaptalk1360812055989.jpg


Chuck
 
Last edited:
On a related note...there is a thread on here in which Dave S provides advice on managing the list that occurs with the 05 to 08 260 Sundancer when getting on plane. Once you figure it out, it is quite easy to manage. Here's the kicker...with my new transom assembly I no longer have the list. This leads me to believe that an ever so slight alignment issue of the transom assembly projects to the outdrive and lower unit in a way that can induce the list. I was amazed how I can get on plane now without having to manage trim tabs or power trim :)

Chuck
 
Last edited:
Well - I'm going through the same right now - both steering pins corroded on a 2008 SeaCore B3. Labour is a lot cheaper where I am - so I am doing the engine pull. But it is still a $3000 job.

But funny enough - the PO kept the boat on a lift as well and keeping a boat on a lift gives a lot of extra issues it seems.

1. Seals/gaskets dry out
2. You can't run A/C unit - so panels start de laminating (in hot weather)
3. Impellers in A/C and Generator are not to happy since PO forgot to close seacock's before lifting - so impellers gets started a lot in "dry condition"
4. And I think you get a lot more growth on salt water cooled things - if they are not flushed when you lift. Lifting them will give more "air" in the cavities in the engine if you don't close the seacocks - giving more oxygen to whatever wants to grow. Genny and both engines fuel coolers have been flushed due to excessive growth and vapour locks.

So IF you are on a lift / trailer - remember to flush - and close seacocks with fresh water in them. And make certain to spray something like Salt Away into B3 steering pin housing from the outside.

To test other B3's for leaky seals on "non cruisers" - just put it into reverse for a few minutes and check inside the steering pin housing. The water pressure from reversing will show leaks almost instantly.
 
ChuckW said:
On a related note...there is a thread on here in which Dave S provides advice on managing the list that occurs with the 05 to 08 260 Sundancer when getting on plane. Once you figure it out, it is quite easy to manage. Here's the kicker...with my new transom assembly I no longer have the list. This leads me to believe that an ever so slight alignment issue of the transom assembly projects to the outdrive and lower unit in a way that can induce the list. I was amazed how I can get on plane now without having to manage trim tabs or power trim :)

Chuck
Click to expand...

Chuck......... As far as I know most of the listing is due to bow steer. When you trim your drive it provides the least "wetted" hull surface and pulls the bow out of the water which in turn minimizes bow steer. I wonder if they changed the position of the "celery stick" ? That could also affect it. Does it come on plane any faster or slower than it used to?

Dave
 
Dave S said:
Chuck......... As far as I know most of the listing is due to bow steer. When you trim your drive it provides the least "wetted" hull surface and pulls the bow out of the water which in turn minimizes bow steer. I wonder if they changed the position of the "celery stick" ? That could also affect it. Does it come on plane any faster or slower than it used to?

Dave
Click to expand...

Nope. My celery stick is forward like always. I specifically checked that.

On boat right now as I type this. It is performing better than ever:thumbup:

Chuck
 
You must log in or register to reply here.

Forum statistics

Threads
113,288
Messages
1,430,071
Members
61,155
Latest member
Dannya1981
Back
Top