1992 mariner 150hp

mudbug 1992

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Does anyone know what prop came on it from the factory. Mine has a 25 pitch on it and it takes forever to get on plane wanting to change props just don't know what I need
 

alldodge

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Welcome
What size prop depends on what boat the motor was installed on. Most would never have use a 25 pitch, would be closer to 19 to 21.

If you know what your WOT RPM and speed is, we could come up with a better guess
 

mudbug 1992

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This motor is on an 18' pro craft. The previous owner installed the 25 pitch prop . I want to go back to the factory prop because I'm having a hard time getting on plain and staying on plain at low speeds
 

alldodge

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If you can find a prop shop many will let you try different props if you buy one first.
 

alldodge

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I don't know where you live but search for prop shops "near me" on google
 

Yegboats

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Can you tell were I need to look
I agree with @alldodge 19P-21P would "probably" be where your pitch needs to be. The boat size,/weight,style,altitude will effect the pitch you need to gain good performance.
A lot of times when you see too high, or low pitch props on used boats it's usually just one they had kicking around or bought for cheap to stick on because the correct one was damaged and they didn't want to sell the engine/boat with a damaged prop.
I would call local boat shop/prop repair shops in your area and see if anyone offers to let you try a couple of pitch props out and return the one/ones that don't work for you.
 

QBhoy

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Hi...
I am not familiar with that particular boat type...but what I can tell you with certainty, is that you would only usually find a 25" pitch prop fitted to a 150 mariner/merc, if the engine itself was on the back of a fairly high performing boat. A boat that's certainly running at speeds well into the 60's or a little more gps. light bass boats and the likes. My wee Glastron cvx16 with her 150 merc for example, is best suited with a 25' laser 2 or similar. that is the kind of application really.
I might also say that most quick running boats like this, with props of that kind of pitch, will also utilise a venting system on the prop. The mercury pvs venting design is an example of this. So if indeed your boat is capable of serious pace top end, but slow to plane (an inherent side effect usually), then the pvs system and similar, is designed for an attempt at lessening the detriment to planing speeds. basically by just venting the prop to spin up quicker...almost like a slipping clutch affect.
 

mudbug 1992

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Mar 4, 2024
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Hi...
I am not familiar with that particular boat type...but what I can tell you with certainty, is that you would only usually find a 25" pitch prop fitted to a 150 mariner/merc, if the engine itself was on the back of a fairly high performing boat. A boat that's certainly running at speeds well into the 60's or a little more gps. light bass boats and the likes. My wee Glastron cvx16 with her 150 merc for example, is best suited with a 25' laser 2 or similar. that is the kind of application really.
I might also say that most quick running boats like this, with props of that kind of pitch, will also utilise a venting system on the prop. The mercury pvs venting design is an example of this. So if indeed your boat is capable of serious pace top end, but slow to plane (an inherent side effect usually), then the pvs system and similar, is designed for an attempt at lessening the detriment to planing speeds. basically by just venting the prop to spin up quicker...almost like a slipping clutch affect.
Turns out I'm getting more and more confused. l reached out to a local prop dealer and he says he can't find info about my prop with out several bits of info that I can't find . Could one of you give me info on a prop that has 25-m stamped on it . It is 14" diameter the best I can tell
 

alldodge

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Back of the prop is next to the nut
s-l1600.jpg
 

alldodge

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I don't know if this is correct but I've seen this comment on a few forums

"Take prop off, lay it on a flat surface and measure the height difference between the leading and trailing edges of a blade, then multiply that number by number of blades. That will give you the pitch."
 

Chris1956

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Mar 25, 2004
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The Procraft looks to be a bass boat type. The Mariner would usually have a 2::1 gear ratio. You would normally run a 19 or 21 pitch, 3 blade prop. I would think a 23P prop would be too tall.
 

Faztbullet

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What brand prop and 21-25 pitch will be about right. Is it a Magnum motor?
Post pics of motor,transon and prop
 
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