1981 50hp Johnson Outboard Prop

couch10&Miriam

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Mar 18, 2009
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I lost my prop in the lake :( In looking at the replacement, they are asking me what pitch it needs to be. I have no idea what to respond. Anyone have any ideas on this one.
 

BigB9000

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Dec 5, 2007
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1,154
Re: 1981 50hp Johnson Outboard Prop

well, how long and heavy is your boat?

What are you using it for, skiing, fishing?

maybe year/type/pic of boat would help
 

5150abf

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Aug 12, 2007
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5,808
Re: 1981 50hp Johnson Outboard Prop

A basic starting point for a 50 is 12 1/4x15 but as Big pointed out that can change if you are running a heavy glass hull or a empty aluminum jon but that is a good starting point.

Ihave your motor and run that prop on an 16' aluminum V hull "bass"( I catfish) boat that is pretty heavy and it does really well.

Get a supply of cotter pins, they are way less expensive than a prop.
 

couch10&Miriam

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Re: 1981 50hp Johnson Outboard Prop

Thank you gentleman for your very quick and informative replies. The boat is a 1981 16ft aluminum Blue Fin. The major purpose that we use this boat for is fishing. We would like to get across the lake as reasonably quickly as we could and back. Attached is a picture of the boat. Additionally, as I read your response, I am assuming it is a 12' diameter, 15 pitch, what does the 1/4 stand for?
 

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5150abf

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Aug 12, 2007
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5,808
Re: 1981 50hp Johnson Outboard Prop

the first number is the daimeter and the second is the pitch or rake of the prop.

That size should work well for you on that boat.
 

Dhadley

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Feb 4, 2001
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16,978
Re: 1981 50hp Johnson Outboard Prop

The second number is the pitch, not the rake. That's something different again. Also if the prop is a progressive pitch style it'll depend on where they measure the pitch.
 

pduquette

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Jun 22, 2007
Messages
999
Re: 1981 50hp Johnson Outboard Prop

Hi , the first measurement listed (12 1/4 ) is 12.25" for clarity... hope that helps . peter .
Ps , my 15 ' mfg that is roughly 500 lbs (factory weight) has a j50 with a 17pitch aluminum prop . This was too steep for the combo so I just got a 15 pitch , but have yet to try it .
 
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