Bravo 3 for 4.3L MPI. Is it overkill?

[smassey22180]

I have seen a few used boats with the 4.3L MPI and Bravo 3 out-drives. Is there major advantage to getting this over the Alpha? These are mostly 18-19' bow-rider boats that are 10 or so years old. I am looking for my next project and want to avoid complexity unless it is worth it. Also, is the MPI any good?

thanks

 

[thumpar]

I have a B1 on my 5.7l. The reason I bought it is because unless I run it low on lube or let water in it is unlikely to break. The shifting is nice without the chatter of the Alpha also. It might be overkill but I like it.

The MPI is a good motor. It has around the power of some of the V8s but in a lighter package.

 

[smassey22180]

Just noticed there are several different Bravo drives. The ones I am seeing are the Bravo 3s with 2 props.

 

[Scott Danforth]

The holeshot with the B3 is so much better than the alpha. Places like lake of the Ozarks where there is a top speed limit work well with the B3. It is fantastic for watersports. It is an upgrade that was most likely custom ordered. Behind a 4.3 with proper maintenance it will last forever

 

[thumpar]

Just noticed there are several different Bravo drives. The ones I am seeing are the Bravo 3s with 2 props.

The is a Bravo 1,2 and 3. The 1 is pretty much just a bigger version of the Alpha with a cone clutch and can handle more HP with higher speed rating. The 2 is usually used on bigger boats with a multiple engine setup. It uses bigger props. The length is longer from the cavitation plate to the prop shaft. The 3 is the one with 2 props on the same drive. It has better holeshot but looses a few MPH on the top end.

 

[achris]

I have the 4.3MPI... I like it. Just a word of warning though. If it a late 05 or 06, check to see if the timing cover is cracked and leaking oil. It was a problem from GM on some of those engines. Just put your hand down on the front section of the engine oil pan and see if you come up with an oily hand. If you do, the oil pan and front cover need replacing.

As for the engine itself. Once I got the oil problem sorted, love it. As I work on a few of these engines and more of my friends are getting them, I bought the Rinda software for the engine diagnostics. Has proved very useful. In short, if you have any problems with the engine (in the future) you're going to need some form of code reader, be it the software of just a simple plug in reader...

Chris......

 

[smassey22180]

I have the 4.3MPI... I like it. Just a word of warning though. If it a late 05 or 06, check to see if the timing cover is cracked and leaking oil. It was a problem from GM on some of those engines. Just put your hand down on the front section of the engine oil pan and see if you come up with an oily hand. If you do, the oil pan and front cover need replacing.

As for the engine itself. Once I got the oil problem sorted, love it. As I work on a few of these engines and more of my friends are getting them, I bought the Rinda software for the engine diagnostics. Has proved very useful. In short, if you have any problems with the engine (in the future) you're going to need some form of code reader, be it the software of just a simple plug in reader...

Chris......

That's funny about the timing cover. I had to replace mine on the 3.0L because it rusted out. Does it really need a new oil pan or just the gasket? I always get the software for my cars so it would be great to get it for the boat. Does it have a standard OBD port . If so I have a code reader for my Android phone.

 

[HT32BSX115]

I have seen a few used boats with the 4.3L MPI and Bravo 3 out-drives. Is there major advantage to getting this over the Alpha? ............. Also, is the MPI any good?

thanks

Absolutely! The Bravo III will handle better at low docking speeds, accelerate better, cruise better and use less fuel at a constant planing speed.

I removed the original OMG 460 King Kobra from my 1987 Four Winns 21' boat and installed a 1997 454 Bravo III.

The engines were rated at essentially the same crankshaft HP but the performance with the Bravo III is nothing short of spectacular.

AND, I would take MPI over a carburetor any day.


Regards,


Rick

 

[Scott Danforth]

That's funny about the timing cover. I had to replace mine on the 3.0L because it rusted out. Does it really need a new oil pan or just the gasket? I always get the software for my cars so it would be great to get it for the boat. Does it have a standard OBD port . If so I have a code reader for my Android phone.

oil pan and front cover actually need to be replaced. a simple gasket will not cut it.

your standard automotive OBD reader will not work on the marine setup.

 

[achris]

That's funny about the timing cover. I had to replace mine on the 3.0L because it rusted out. Does it really need a new oil pan or just the gasket? I always get the software for my cars so it would be great to get it for the boat. Does it have a standard OBD port . If so I have a code reader for my Android phone.

Since mid '96, 4.3s have a composite cover. It doesn't rust out, but if the sump (oil pan) is one of the faulty ones, it cracks and leaks oil. And the only way to stop a new cover cracking is to replace the sump at the same time... Completely different set up to the 3 litre. The MPIs don't have an ODB port, it's a Merc specific 'diagnostic connector', and a standard automotive code reader is of no value.

oil pan and front cover actually need to be replaced. a simple gasket will not cut it.

your standard automotive OBD reader will not work on the marine setup.

Thanks Scott, see above..

 

[alldodge]

The B3 is the way to go with hole shot and docking as others have mentioned. The real biggy in docking is with the B1 or 2 when you put them in reverse the prop rotation will pull the boat sideways as you back up. The B3 is much more straight back due to counter rotating props cancelling each other out.

 

[smassey22180]

Thanks to all for the great info on the B3 and the 4.3L MPI. I just found out the boat I was thinking about has bottom paint on it. I was hoping for a garage queen.

 

[Lou C]

If I could find a boat with that set up for sure I'd buy it over an Alpha, for the smoothness of shifting and the better manuverability.
Consider this, if you got a Volvo powered boat the SX could be had with a DP lower even on the smaller engines, and it wasn't that unusual to see 4.3s with that set up. Same advantages, the only drawback is the added complexity of the dual prop set up (ie if you ever hit bottom, the prop shaft/props are a lot more expensive than a single prop drive would be). But those events should be covered by insurance.

 

[agallant80]

The only thing about the Bravo3 is you are looking at 5K to replace if you have a disaster vs 1K for an alpha. I love by B3.

 

[thumpar]

The only thing about the Bravo3 is you are looking at 5K to replace if you have a disaster vs 1K for an alpha. I love by B3.

Insurance is cheap.

 

[HT32BSX115]

The only thing about the Bravo3 is you are looking at 5K to replace if you have a disaster vs 1K for an alpha. I love by B3.

That might be a bit of an exaggeration....... While I did find brand new Bravo III drives for "$4995.00" I didn't find any NEW Alphas for $1000. Even the SEI drives "NEW" are approx $1300 making a new (Mercury) Alpha somewhat more.........

I replaced my previous OMG King Kobra in my old 21' FourWinns with a Bravo III........... The performance improvement is well worth it!! I wouldn't go back to ANY single prop drive after having this thing!

Cheers,


Rick