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Old 07-09-2008, 06:49 PM   #1
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Change from Bravo 3 to Bravo 1

Hi
Can I get away with just swapping the legs over ? or is a compleatly different set up, will I have to change the transom plates I.e remove complete leg set up and start again? any help advice would be great .
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Old 07-09-2008, 09:19 PM   #2
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Boat name: bernico cat
Boat make: bernico 26 cat 2x 2,5,s
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You can swap any bravo style drives to a bravo gimball housing .
So your bravo 3 can be swapped for a bravo 1 without any modifications .

The lower unit alone can be done too ,the upper units are the same ,but watch the gear ratios,different bravo units have different ratio,s ,

when using a single diesel engine with an heavy boat ,you will probably find that you will have a significant higher propellor slip number.

If so ,try to find a Maximus propellor ,that prop was the only prop that was working ok with my Bravo 1 /diesel setup with single engine.

A Hydromotive p 5 x will do fine also.

good luck
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Old 07-09-2008, 10:04 PM   #3
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Boat name: Scarab Racing
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Hi sterling
So from what you are saying I can just swap the lower gear case or have I got that wrong.
How did you get on with the props I sent you?
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Old 08-09-2008, 06:27 AM   #4
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Country: netherlands
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Boat name: bernico cat
Boat make: bernico 26 cat 2x 2,5,s
Engines: merc,s 2,5 EFI,s
Cruising area: ijselmeer

Join Date: Dec 2005
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yes you can swap lower units ,but ceck this first :http://www.go-fast.com/sterndrive_gear_ratios.htm

Watch the end gear ratio if swapping components .

the props you send were too much pitch ,I couldn,t get my boat to plane anymore ,so I sold them.

A.J
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Old 10-09-2008, 03:01 PM   #5
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Country: England
Location: Surrey
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Boat name: Scarab Racing
Boat make: Scarab 27
Engines: Yanmar 315
Cruising area: South coast

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Location: Surrey
Posts: 200
Hi Sterling
What pitch were you running on your yanmar / mercruiser ? was that one with the bravo 3 or 1?
I've been offerd a bravo 1 with a 1.5-1 ratio so looking at the figures if I come up a bit on the pitch to 26-28 I will be back to the same as the 1.36-1 with the 24s.
Do you think this is a wise move or should I keep looking for a 1.36-1 ?
Any thoughts or advise?
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Old 10-09-2008, 04:26 PM   #6
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Country: netherlands
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Occupation: truck repair
Interests: fast boats/porches
Boat name: bernico cat
Boat make: bernico 26 cat 2x 2,5,s
Engines: merc,s 2,5 EFI,s
Cruising area: ijselmeer

Join Date: Dec 2005
Location: Mijdrecht/holland
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Difficult to say what to do ,I found that all I knew about boat /prop/ratio/sort drive etc is all different when comparing with diesel engines.

I cant say which drive would be better for your boat ,
I used a B1 with 1,5 ratio witha 26 pitch maximus ,and now I have a B3 with 1,65 and 28 pitch .

results were about the same ,the only thing is I have a little better cruising speed with the B3 drive .
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Old 10-09-2008, 09:44 PM   #7
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Quote:
Originally Posted by scarab racing View Post
....I've been offerd a bravo 1 with a 1.5-1 ratio so looking at the figures if I come up a bit on the pitch to 26-28 I will be back to the same as the 1.36-1 with the 24s....
Matching the prop pitch and gear ratio either way will load the engine similarly but a lower pitch prop will be a tad better at low speeds and a higher pitch prop a tad better at higher speeds - For comparison, provided the props are identical types of course. I suppose it depends whether your boat needs a bit of low speed help.
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Old 11-09-2008, 12:44 PM   #8
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Country: England
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Boat name: Scarab Racing
Boat make: Scarab 27
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Changing the drive leg is being put on hold as just got back and the engine is making a rather nasty noise so going to remove engine and strip down see what we can find. It sound like big end nasty knock from low down. If enough pennies left over will go for the leg change, but waiting to see what I find.
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