Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

  • Yes, definitely!

    Votes: 1 14.3%

  • Probably, if the price was right

    Votes: 5 71.4%

  • I wouldn't benefit from 2 props in my application

    Votes: 0 0.0%

  • No, just not interested

    Votes: 1 14.3%
  • Total voters
    7
  • Poll closed .
RogersJetboat454

RogersJetboat454

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

Howard Sterndrive said:
I'd be interested if it was under $1500... not sure that's a fair price, but if they could make it take whatever propsets are the most affordable I could stomach another $400 or so for those.
I posted it on their forum last year:
http://www.shopsei.net/vbforum/showthread.php?t=1353
no responses....
Click to expand...

Not a merc guy... so I may be disqualified :D... but would the guts of an alpha upper gear box be able to handle swinging the extra rotating mass?
 
Don S

Don S

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

I posted it on their forum last year:
http://www.shopsei.net/vbforum/showthread.php?t=1353
no responses....
Click to expand...

LOL, no wonder there were no responses,
If you knew how a a duoprop lower unit worked, you would understand why it can't be used in a Alpha drive.
The shifting HAS to be done in the upper for a DP to work.
 
Howard Sterndrive

Howard Sterndrive

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

hmm, yeah...
I guess it might have to be a whole replacement drive with a shifting upper.
I'm quite sure shifting and CR shafts could be made into one gearbox (lower), but there would be a lot going on in there and hard to say if the engineering could be done cost effectively.
 
Don S

Don S

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

I guess it might have to be a whole replacement drive with a shifting upper.
Click to expand...
They call those Volvo and Mercruiser Bravo III drives.

I'm quite sure shifting and CR shafts could be made into one gearbox (lower),
Click to expand...
If you looked at how a DP lower works, and how an Alpha drive shifts, you will see why it won't work.

The fact that you think this can happen for only $400 more than a reverse engineered, chinese built alpha cloned lower can be sold for is almost laughable.
For SEI to to it, a real outdrive company would have to invent the system so they could copy it when the patent runs out.

Personally, I don't like Mercruiser drives or engines anymore. Only due to how complicated and impossible to work on they have made their fuel and cooling systems in the past few years. But SEI is nothing more than cheap junk clones. And yes, I have installed them and worked on them.
 
Howard Sterndrive

Howard Sterndrive

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

well, a few years ago there were lots of threads around various message boards where people were told there's no way to replace a Cobra with anything else...
now people are putting Mercruiser copies on there.
That's what made me think SEI... they came to the table with another option

I didn't suggest they could do it for $1500 or any amount of money... that's just the price point for me. More than $1500 I wouldn't be interested. I don't boat enough to justify more.
 
Don S

Don S

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

It wasn't an impossible concept to change a bellhousing and shift cable to install a different drive, Volvo did that in the mid 90's with the SX conversion. SEI designed a bellhousing to use the Alpha I Gen II clone.
But that is completely different from making a dual prop drive for an Alpha I GII drive. The fact that the same gears running at the same time in opposite directions in the lower unit for a DP drive are the same gears need to change direction using a dog style clutch. You can't do both.
 
oops!

oops!

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

Don S said:
Personally, I don't like Mercruiser drives or engines anymore. Only due to how complicated and impossible to work on they have made their fuel and cooling systems in the past few years. .
Click to expand...

wow.....this is quite a statment.....

ill have to have a look at this......but usually i only work on 08 or older......the new stuff is done by the marinas that sold them
 
79Merc80

79Merc80

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

Who is this SEI and do they have a web site?
 
M

muc

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

Yamaha did it with the DX150 outboard. So it can be done.

Never seen one much less worked on one.

Only way I can see it working is to only have one prop powered when your in reverse. So you would lose the backing up straight advantage that you get with duo prop/bravo3.

It didn't take the market by storm and I'm not even sure they still make it. That makes me think there was a price or durability issue.

Duo props don't really help a enough to justify the cost until the boat gets 23ft or bigger and at that point you get into the need for more horse power/thrust than the alpha was designed for anyway.
 
Howard Sterndrive

Howard Sterndrive

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Re: Alpha One owners... if SEI made a Duoprop Lower unit, would you consider it?

DX150 - neat... looks like it has two separate dogs...not shown in this pic, but the shift linkage looks like most any other outboard
dx150lower.jpg
 
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