Bravo III duo prop corrosion

[jwilkey84]

I was looking at a 2001 boat with a bravo III Duo prop setup. Then I ran across some info that said to watch for corrosion on these. The boat has only 180 hrs on it and it's only been in fresh water. And I don't think it was prly ever left in the water over night. So what do I need to look for when I go to see it? This will be my first "real" boat andnthe last thing I want to do is buy some one else's headache. Esp on something that requires 2 props ! The boat is a 21' sea ray sundeck with the 5.0 and bravo III. It's a 2001 so I think it's a 5.0 TBI, NOT mpi. Would this be a good setup on this boat?? Is tbi a good move or should I hold out for a 5.0 mpi ? any real cost of ownership difference on bravo III VS a single prop setup other than the cost of two props? Is the bravo III more or less fuel efficient? I also understand these props need to be removed annually at least to ensure they don't sieze to the shaft? If the props are siezed do I walk away from the deal ?

 

[alldodge]

The B3 has more stainless (2 props) in the water so keeping corrosion in control is an issue but not for a boat that sits on a trailer. If it is left in the water and connected to shore power you need to check if the Mercathode is producing enough voltage.

The B3 is heavier but more efficient then the B1. Props do not seize on the shaft anymore for a B3, then a B1 or even an Alpha for that matter. All props should be removed yearly to check for fishing line and anything else wrapped on the prop shaft, and for inspection. The place were corrosion on the B3 happens is under the front prop on the carrier. If some is found, just clean it up and repaint as necessary. There is no difference in cost of ownership so long as nothing breaks, like when something is hit. I would take a B3 over the B1 with what your looking at.

I would take either TBI or MPI, but the MPI provides a tad more power

 

[harleyman1975]

It will be much nicer at non planning speeds...no wandering.

 

[jwilkey84]

So let me reveal my ignorance ...what's the carrier? Do I physically need to remove the props to inspect for corrosion? Any special tools needed to remove props...all ever worked on were outboards from the 70's and it's been a few years!

 

[tpenfield]

There is a fair amount of sensationalizing about the earlier day Bravo 3 outdrives. As AD said a lot more stainless steel in the water than what people were initially used to, so the anode protection and maintenance were often not enough. Are you trailering the boat or keeping it in the water?

The bigger risk is for boats kept in the water. Salt water kept boats may not be at any greater risk. because the salt guys are much more cognizant about corrosion protection. I bought a boat that was kept in fresh water its whole life and the bearing carriers (that sit in front of the props) were pretty much trashed from lack of anode maintenance.

​Anyway, look for pits and powdery areas on the outdrive just to see if it was well maintained.

 

[alldodge]

No problem-o, the carrier is what holds the rear bearings and one of the two seals. There are two seals one for each shaft. Yes to inspect the props would need to come off. The inner nut is 2 13/16 and outer nut is 1 7/16

 

[jkust]

A couple thing...Sea Ray, even up to some of their larger Sundecks seems to come with a 5.0 when you'd expect to see a 5.7. I am at a loss as to why that is the case...I've seen this discussion on the Sea Ray sight. Maybe it is just a Minnesota thing...I can't figure it out. Anyway, because 2001 is the final year of TBI production when MPI took over in 2002 for small blocks and V6's, I would look for a 2002 or newer with MPI. It is more HP as mentioned but also capable of Smartcraft with the additional technology. Oddly enough then, It seem Sea Ray was an early adapter of Smart Craft guages on their boats when the competitors don't seem to ever have them on those early MPI 2000's models yet the Sea Ray will still have a base 5.0. My logic on MPI aside from it having more modern technology is that it is 2017 and there are millions of early 2000's boats out there with MPI ready to be negotiated. If it was say 2007 and MPI in small blocks (because MPI was available on big blocks several years prior to 2002) had only been around for 5 or 6 years, then I'd have a different take on TBI.
As it turns out, my sig boat has the 5.7 MPI and the previous owner must be the only person to order this boat with a Bravo 1 instead of a Bravo 3. I guess I forgot to ask him why he went B1 when the B3 price was negligible once you got to the Bravo level. Anyway, it tends to bow wander and annoys me at times and the low speed handling could've been improved with a B3 as well but the B1 is supposed to get a couple more clicks at the top end which is when you really don't 'need' it.
The other thing is that those 2002, 2003 ish years a lot of boats got a massive redesign up to the next generation of hulls and technologies. It's when the 90's technology went out and the next gen was ushered in. Starboard replaced wood, flow through seat materials became more widely used, fiberglass floors became standards along with snap in carpet. That is to say that just a couple years newer boat will get you a next gen boat that was likely made for many more years and also won't be as dated.

 

[jwilkey84]

What is smartcraft? As far as I can tell both the 01 and 03 21' sundecks had snap out carpet. And have fiber glass floors. I would imagine no wood construction. Not sure though. Surely on the 21' boat the 5.0 tbi or mpi would be sufficient? I don't think I want a 5.7 guzzler. I think these sea rays are around 3500 lbs. I'll be trailering the boat every trip and just looking for a nice boat for an afternoon of tubing and skiing

 

[jwilkey84]

I must say I like the look of the newer four winns boats with the rear facing loungers in the back of the boat but they're out of my price range

 

[jwilkey84]

So are there any drawbacks with a 5.0 mpi? In some sense I could appreciate the tbi as it's prly cheaper to work on. Buy on the other hand ...does the mpi hardly ever need worked on...esp with only 88 hrs on the engine ?!

 

[alldodge]

What is smartcraft?

Digital data which the ECM can store and use, also adds another layer of things that can go wrong and/or need fixing. Good stuff, just not necessarily the best stuff IMO.

Surely on the 21' boat the 5.0 tbi or mpi would be sufficient?

For the most part Yes, but remember when you put a heavy load on a boat the more power it needs. Think about what you want to do with it. I have a 23 footer with a 454 carb and B1, it will pull any toy with several folks aboard. Another guy at the dock with the same boat 5.7 EFI and B3 it does fine running by its self and a few folks, but put toys and a load and it has nothing much left to get it up.

I don't think I want a 5.7 guzzler

While the bigger the motor the more gas it uses, can only use that with a regular load. First a boat doing really well may get just under 2 miles per gallon (MPG). My 454 having fun pulling toys will use less gas then the same boat with a 5.7 doing the same. Running with regular load the 5.7 will burn less then the 454.

A boat is made to have fun with, so if your boat doesn't do what you want it to do, then the fun meter starts sagging. So back to the 5.0, it may use more fuel then the 5.7, it all depends on how your going to use it. Also keep in mind that a 4.3 MPI is about the same HP as the EFI 5.0

As the old saying goes and is still true today, there is NO replacement for displacement

 

[Scott Danforth]

Surely on the 21' boat the 5.0 tbi or mpi would be sufficient? I don't think I want a 5.7 guzzler.

marine motors generally burn about 0.4# of fuel per hp per hour. no mater if the motor is a 3.0 or a 8.2. so if both motors are putting out 200hp for the load at hand, they both are burning 80# of fuel or 12.7 gallons (6.3 #/gallon)

the amount of power the hull needs at a certain load and at a certain speed against a certain wind/current determines your fuel consumption. in many cases just tooling along, the larger motor is slightly more efficient at pushing the boat along than a smaller motor and may actually use less gas until you move the throttle and command more power.