How to tell if Bravo or Alpha Drive?

martin bird

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Hi: I'm new and clueless - sorry. But I guess experts don't need forums such as this. So I appreciate your patience. I posted yesterday a question about winterizing my 2010 Glastron w/ Merc 4.3 MPI boat. One reply asked me if it was a Bravo or Alpha drive. I confessed I don't know. Where does one look? What is the difference. I do know that it is a raw water cooled boat. And I'm still not sure if for winter which hoses if any need be removed in addition to the three (3) blue drain valves/plugs. Thanks.
 

Fun Times

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Re: How to tell if Bravo or Alpha Drive?

Hi: I'm new and clueless - sorry. But I guess experts don't need forums such as this. So I appreciate your patience. I posted yesterday a question about winterizing my 2010 Glastron w/ Merc 4.3 MPI boat. One reply asked me if it was a Bravo or Alpha drive. I confessed I don't know. Where does one look? What is the difference. I do know that it is a raw water cooled boat. And I'm still not sure if for winter which hoses if any need be removed in addition to the three (3) blue drain valves/plugs. Thanks.
Most likely you will have an alpha drive, To be sure though you could look at your stern drive, it should have a sticker on the drive that says what it is. If you can't find the info on the drive then do you have the engine, drive, or transom serial number/s handy?
 

Don S

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Re: How to tell if Bravo or Alpha Drive?

Post a picture of the drive, or post the serial number of your drive. With an MPI engine, it could easily be either.
 

tpenfield

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Re: How to tell if Bravo or Alpha Drive?

A picture of the outdrive will tell, but I would be surprised if it was not an Alpha. Bravo drives are usually matched up with the big V8's.

Alphas have the impeller inside the outdrive, similar to an outboard motor. The bravo drives have the impeller in a separate pump that is attached to the engine.
 

Don S

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Re: How to tell if Bravo or Alpha Drive?

You guys must live sheltered lives that don't see any 4.3MPI engines with Bravo drives.
 

achris

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Re: How to tell if Bravo or Alpha Drive?

A picture of the outdrive will tell, but I would be surprised if it was not an Alpha. Bravo drives are usually matched up with the big V8's.

Alphas have the impeller inside the outdrive, similar to an outboard motor. The bravo drives have the impeller in a separate pump that is attached to the engine.

Sorry, Alphas can have engine driven seawater pumps too....

You guys must live sheltered lives that don't see any 4.3MPI engines with Bravo drives.

Agreed...... :D
 

HT32BSX115

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Re: How to tell if Bravo or Alpha Drive?

Searay also routinely puts Bravo III's behind the 4.3L twin-engine Sundancers
 

Don S

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Re: How to tell if Bravo or Alpha Drive?

I'll be placing my odds on it having an alpha stern drive on this one.

The original post is all about wanting to know what drive he has, he doesn't know.
He does not want to know the odds of having an Alpha over a Bravo, he wants to know for sure.

Serial numbers of the drive are the best way to go to find out for sure. Guessing and Flipping a coin sure isn't going to answer the question with any kind of accuracy, neither is discussing which one is more prevalent in your area.

He wants to KNOW what he has, Not the odds of one or the other.
 

4js

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Re: How to tell if Bravo or Alpha Drive?

Stone. Cold. Busted. Funny Don!
 

achris

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Re: How to tell if Bravo or Alpha Drive?

As the 4.3 was only configured with either Alpha One, Bravo 2 or Bravo 3 a couple of simple questions will solve the mystery....

1. Does the drive have twin counter rotating props on the same shaft? (Bravo 3)
2. Is the propeller a 20" diameter? (Bravo 2)
3. The anodes on the end of the trim rams, short or long? (short = Alpha, long = Bravo)

The other way is to post either the serial number or (best way yet) a photo....

Chris.........
 

martin bird

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Re: How to tell if Bravo or Alpha Drive?

Well i quit being lazy and went and looked. It is a.............(drum roll) Alpha One. Whatever that is. Am I assuming correctly that the Alpha One is for smaller boats that aren't as expensive as the "Bravo" Drive boats? Not as robust as the Bravo? Anyway it is what it is. I've got a lot to learn. Thanks
 

Lyle29464

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Re: How to tell if Bravo or Alpha Drive?

Not as robust as the Bravo? Anyway it is what it is. I've got a lot to learn. Thanks

It is fine. They will hold up to a much bigger engine. Just keep it serviced and it will be there many years.
 

searay4me

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Re: How to tell if Bravo or Alpha Drive?

What a great and funny back and forth.

Thank goodness for the information these people have and are willing to research; and the patience they have for we who don't.
 

tpenfield

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Re: How to tell if Bravo or Alpha Drive?

Well i quit being lazy and went and looked. It is a.............(drum roll) Alpha One. Whatever that is. Am I assuming correctly that the Alpha One is for smaller boats that aren't as expensive as the "Bravo" Drive boats? Not as robust as the Bravo? Anyway it is what it is. I've got a lot to learn. Thanks

Thank you Martin. You have ended the suspense and lengthy discourse of the realm of possibilities.

The Bravo drive is rated for higher horsepower, etc. and so expensive that most retailers do not want to tell you how much it costs :)
 
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