Prop Pitch

zach103

Commander
Joined
Mar 11, 2008
Messages
2,233
How do i know what pitch i need for my prop.. using the marine store i got to the engine i have but it came up with picthes from 9-24. what one do i need?
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Prop Pitch

Which one do you need? The one that puts your top rpm where you want it with an average load.

A little more info is needed. What motor, boat, use and info on props already tried?
 

zach103

Commander
Joined
Mar 11, 2008
Messages
2,233
Re: Prop Pitch

sorry..

its an 86 Johnson SPL 90hp. on a 86 Larson Senza V-175BR..
max hp is 150 and i know the 90 is a little low but i don't have the money for a new engine right now..

average load is prolly 3 -4 adults. no real water sports. just kind of lounging maybe the ocasional tubing.

any other info you need im happy to tell you
 

Tacklewasher

Lieutenant Commander
Joined
Sep 18, 2002
Messages
1,588
Re: Prop Pitch

Best way to figure out what you need is to provide comparison info on what you have.

So, which prop do you have?
Alum or SS?
What size?
What pitch?
What is your top speed (gps) with this prop?
What is the RPM @ WOT?
How do you boat? Pulling skiers, tubers or looking for top end speed?
What is your current prop doing that makes you want to change it?
 

zach103

Commander
Joined
Mar 11, 2008
Messages
2,233
Re: Prop Pitch

i was told to change this one or get it repaired because its giving me vibrations in the hull on acceleration
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Prop Pitch

What size is it? What were the top rpms before it was damaged? Top speed?
 

zach103

Commander
Joined
Mar 11, 2008
Messages
2,233
Re: Prop Pitch

im not sure the size i guess this thread will be stalled for a while. lol. im at school i can get the size when im home on friday.. tach was stuck at 7 when we bought the boat boat.. its on the winter parts list. i dont know the top speed. weve only had it a year or so and last year the shaft broke. i got up to 30 this year but using the speedo from the boat. i need to borrow a gps.

i usually go out just to relax kind of thing. i occasionaly pull people in the tube. im really looking for more speed.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Prop Pitch

My guess is that it probably has a 17 on it or maybe a 19. Really hard to say. Could be either and either one could be set up wrong, or at least not as good as it should be. If it's been sitting for more than a month I'd suggest cleaning the carbs first before testing.
 

zach103

Commander
Joined
Mar 11, 2008
Messages
2,233
Re: Prop Pitch

the guy did that the week before we started it back up..but how do i do that so i know how to for the future.. i remember seeing a 13 i think but that might be something else
 

zach103

Commander
Joined
Mar 11, 2008
Messages
2,233
Re: Prop Pitch

alright its a 15 i believe i got this off of it 3 3/4 x 15
than 391198?

so is 15 the wrongs size if your guessing 17 and 19??
 

Randybeall

Petty Officer 1st Class
Joined
May 2, 2008
Messages
319
Re: Prop Pitch

You can probly save yourself some time and money by taking that prop to a prop repair shop. Not only can they tell you how much it would cost to repair if that is possible, they can measure it and tell you exactly what it is. Just a thought, I never seem to have as much money as the BOAT wants.
 
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