Prop size I should be using

Momboy007

Seaman Apprentice
Joined
Jul 24, 2017
Messages
37
Hello All,
I have a new to me 1997 Celebrity 180 Bowrider with a 4.3 Mercruiser, 2 bbl.
I do not know what prop should be on the boat, it currently has a 4 blade prop which Seems too big, does anyone know what should be on this boat?

Thanks in advance,

Rick
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,309
Likely a 3 blade 21" or 23" would be standard.
Really need current specs like max rpm when wot and trimmed up....speed at those revs and gear ratio stamped on drive.
At a guess, 21" would be a decent all round. Likely 4400-4800rpm is your ideal Rev range.
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,309
Depending on age....its usually up on the top section and on the mercruiser sticker band that runs round the very top of leg. Will likely say something like
"Gear ratio 1.81" or similar. The stated being the most likely for your engine and drive.
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,309
Why do you think the prop you have is too big ? You mean physical size or that it isn't performing right or the revs are too low ?
You shouldn't really need a 4 blade on your boat I'd say....the go to prop for many with your application is a black max 21 " 3 blade for all round or a 23" for top end speed bit a lesser ability to accelerate or water sports ability.
A decent stainless like a laser 2 or similar is well known to suit that set up and should see you to around or just under 50mph, all being well and running light..even with the 2 barrel carb.
 
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