Bought a 14' boat, 9.9 Mariner with a busted prop.

Joined
Apr 14, 2015
Messages
9
It's a very light boat. The motor comes out as a 1990 model. I don't know squat. I bought one of these: http://boatpropellers.iboats.com/Ma...0_0910_Propeller/222/36441/?cart_id=752789365 I don't know what pitch is, unless it's used on a roof. I wanted something to move me ok alone, or when I've got 300lbs more of family with me. I'm old, not a speed demon. Did I do OK? Oh, and I just bought the prop. There is some kinda middle part they sell also. Do I need one of those? 8 spleen something? Thanks for any info people. I'm a minnow..:)

- Man-Overboard
 

Bondo

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Staff member
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Apr 17, 2002
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71,095
Ayuh,.... Welcome Aboard,.... What's the pitch, 'n size of the busted up prop,..??

It'll be stamped on it, or under the nut,......
 

steelespike

Supreme Mariner
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Apr 26, 2002
Messages
19,069
The Hustler is said to out perform other al. props. It does require the hub.that you didn't order.
What criteria did you use to select this prop?
There are 2 other good props for less money The Solas Amita or Rubex.
Rubex is the same as the Amita but with a removable hub like the Hustler.
What is the horse power rating of the boat?What is the actual dry weight of the boat?
What is the total load including the motor,gear, and people?
What is the width and length of the boat.
There are what I call small 14 footers and large 14 footers.
Sometimes you can judge the size by the hp. rating. and capacity.
A larger 14 might be rated for 25 or 30 hp a smaller 14 for about 10 hp.
The larger 14 may respond better to added weight.
Your 9" pitch may work for a load but may over rev with a light load.
It is usually suggested to have an induction tach for rpm check and a GPS for accurate speed.
It's important the motor can rev freely within its rated rpm range.
Once the correct prop is selected your free to operate at what ever rpm suits you.
 
Joined
Apr 14, 2015
Messages
9
Sorry for the late response. Your answers are great!
What criteria did you use to select this prop?
Reading a lot on the interweb, and failing to notice that iBoats price was WITH hub and Worst Marine was WITHOUT hub so I thought I was getting a deal :( Good news is the motor starts first pull every time. And the prop spins. Just for 5-10 seconds. I can't see where it would pull in water for cooling, but I don't want to burn it up.

My existing prop is a 3 blade with these numbers:
A 12
7 9P Except the 7 is upside down?!?!?! It's not an L though, it's an upside down 7 for sure. If the 9P means 9 Pitch then my new one is the same. I'm hoping that it will push the boat decent with just me 175# or so in it, and also decent when I add my 240# of wife and 2 kids also. I bought the #210 prop hub I needed. The local Worst Marine had one for $26. I won't have the prop until Monday. After much hard looking at my boat I think it is a very old MirrorCraft. It has big M's on the top of the 2 rear corners. I don't trust the Craigslist guy I bought it from so I'm going to change out the existing gas. Oil at 50:1??? And maybe a dab of SeaFoam before I take it out.

- Man-Overboard
 
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Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
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12,345
Must tach that engine with an induction Tiny Tach or Harline tach with you alone and lightly loaded boat, check new prop if inside min-max wot parameters factory stated for that engine, ideal to be between mid to max rpm.

A 9.9 HP is a poor performer for a 14 footer, usually 20-30 HP, will need to maximize prop for best overall water performnce with family. Fun starts when boat planes, fast displacements speeds are boring ones.

Bear in mind that after you dial best prop pitch for family leisure will need to stay away from full throttle operation as for the engine not to over rev if boating solo.

Happy Boating
 
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steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
A healthy 9.9 will make speeds about 20 lightly loaded on a 14 ft.Utility.
If the boat is what I call a "small" 14 it may struggle with a load.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
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12,345
If it's a 2 strokes, could pass that 9.9 to a 15 HP, both are 250 CC powerheads with different restricted carbs. a 15 will work much better on a14 footer. You could maximize prop pitch too and have more power to plane faster that family combo.

Happy Boating
 
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