Prop Question - 75 hp Johnson

johnrob281

Recruit
Joined
Aug 31, 2003
Messages
3
I have and 1981 Johnson 75 HP and the prop on it lists the size as 13 X 19. This seems like a larger prop than needed. Is this the correct one?<br /><br />Thanks in advance for your help.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Prop Question - 75 hp Johnson

Dont know. Cant read the tach from here. Move it to the left a little.<br /><br />A 19" on a 13' Checkmate may be a tad small. A 19" on a 22' Aquasport may be a tad big.<br /><br />Seriously, tell us your top rpm with an average load and true speed and we'll calculate slip % for you. We can go from there.<br /><br />Good luck!<br /><br />PS;<br />Moving it to the left didnt help.
 

Spidybot

Lieutenant Commander
Joined
Apr 4, 2002
Messages
1,734
Re: Prop Question - 75 hp Johnson

Dhadley, you.... made my day, again ;)
 

johnrob281

Recruit
Joined
Aug 31, 2003
Messages
3
Re: Prop Question - 75 hp Johnson

Dhadley...Great Answer, although not the one I was looking for!<br /><br />The motor is new to me so I'll check out the RPM's etc this weekend and give you more info.<br /><br />Thanks,
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Prop Question - 75 hp Johnson

Cool! The rpms are key. Let us know -- we'll get you going!<br /><br />BTW -- what kind of boat have you got there?
 
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