Looking at Formula with bravo drives...No impeller in drive??

crazy charlie

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Looking at a Formula with twin big blocks and bravo drives.The boat is a 1998 so I think the Bravos are the not the current bravo 3s but the bravo 2s instead.I am an alpha guy and have been for 30 years so very familiar with impeller in the drive maintenance.Very familiar!! I am told the bravo does not have an impeller and does not require the same maintenance.The pump is on the engine instead,I guess similar to circulator pump.Can anyone enlighten me a bit on how the water is introduced to the engine.Thanks Charles
 

alldodge

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The boat would have B1 drives not B2's. On all Bravo drives the water pump is externally belt driven, and mounted on the starboard side down low. The impeller should be replaced every 2 to 3 seasons.
 

Scott Danforth

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B2's are single prop drives for trawlers and houseboats (giant prop)
 

tpenfield

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Yes, as AD said. It is called a sea water pump and runs directly off of the engine via a belt and pulley. It sucks . . . No literally, it has a tighter fit for the impeller and creates a bit of suction and is pretty much self priming since it sits low in the engine bay and is not far above the water line.

What model Formula are we buying? :).
 

crazy charlie

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Thanks guys,I will have to take a look.It is a 31PC .The owner is not sure if it is fwc or rwc.I will have to find a pic,can't ever remember seeing one on the block before.Like I stated,I am an alpha guy.Charlie
 

alldodge

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In the bottom right of this pic is the pump, and being a 98 it should also have a serpentine belt.
Photo618.jpg
 

crazy charlie

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Nice chandelier !! thanks.So should i assume it is no more difficult to service than replacing the impeller in my alpha drive?
 

alldodge

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Nice chandelier !! thanks.So should i assume it is no more difficult to service than replacing the impeller in my alpha drive?

It's actually easier to replace, that is IF you can get to it. I have to remove the alternator, oil lube bottle and hang upside down, a 31PC should have more room then I do.
Photo620.jpg
 

tpenfield

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coolant cooled engines on my F-330SS So if you see a big heat exchanger on the top/front of the engines . . . then it is 'FWC', aka closed cooling.

IMG_1338.jpg
 

savetexomabeaches

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lol ran into a bravo needing the impeller replaced today.. man oh man how I wish they were in the drive. Down at the very very, all the way down starboard side. plastic housing, don't bust it
 

HT32BSX115

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plastic housing, don't bust it
Yeah, you'll do that once..........

I busted mine, and then installed A stainless steel housing!
625-4178.jpg


No more breakee!

Cheers,

Rick
 
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thumpar

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I have been wanting the Hardin housing for mine. The Globe impeller would be a great add on. That should last awhile.
 

wrvond

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Looking at a Formula with twin big blocks and bravo drives.The boat is a 1998 so I think the Bravos are the not the current bravo 3s but the bravo 2s instead.I am an alpha guy and have been for 30 years so very familiar with impeller in the drive maintenance.Very familiar!! I am told the bravo does not have an impeller and does not require the same maintenance.The pump is on the engine instead,I guess similar to circulator pump.Can anyone enlighten me a bit on how the water is introduced to the engine.Thanks Charles

The B2 is quite a bit beefier than the B1 and is still a "current" drive. B3's are popular, but have been around just as long as the B2's.

B2's are single prop drives for trawlers and houseboats (giant prop)

I have a Bravo II drive, and I'm pretty sure my boat isn't a trawler or a houseboat. the ratio is 2:1 prop is 17.5x23 WOT is 4600 RPM.
 

alldodge

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There has been a few threads on the run dry type and what I remember (suffer from CRS) but they work very well in Alpha's not so well in Bravo's.

BTW, if you get the stainless housing you also need the hose fittings.
 

Bondo

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but they work very well in Alpha's not so well in Bravo's.

Ayuh,.... My Bud, Bob claims they don't move the volume of water in a Bravo,.....

I've run one for 'bout 10 years in my ole Alpha 1,...
It was still pumpin' just fine when I swapped the drives last year,....
 

HT32BSX115

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There has been a few threads on the run dry type and what I remember (suffer from CRS) but they work very well in Alpha's not so well in Bravo's.

BTW, if you get the stainless housing you also need the hose fittings.
you do indeed. I used brass fittings.

After having the housing break at the lake. I'll never go back to plastic!
 
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