buying a new prop new help

[ILMuskieHunter]

i need to buy a new prop and the 4 options that are on this site and 9" pitch, 10" pitch, 11" pitch, and 12" pitch and i have no idea what the difference it going on a 1965 18 hp Evinrude and i know nothing and I'm tiring to learn everything i can about it know so thanks

 

[Bondo]

Re: buying a new prop new help

Ayuh,... So what prop is on the motor Now,..?? How does it run,..??

A copy of the Same is probably the way I'd go...

 

[steelespike]

Re: buying a new prop new help

A prop shop may be able to repair your prop.The motor came with a 9 1/4(diameter) X 11" (pitch).Pitch is the key number diameter follows design.Picking a prop is like selecting a single gear in a car to do everything.There may be prop numbers on the barrel near the base of the blades.Low pitch numbers are like low or second, higher numbers like high gear or overdrive.You really need a tach to get the motor set up right.
A tinytach is reasonable and easy to install.And one for your motor will fit any 2cylinder 2 stroke.
Tell us the details of your boat and performance. Typical load and activities.
the 18 is capable of speeds up to 27 mph on on boats it is intended for.

 

[ILMuskieHunter]

Re: buying a new prop new help

yea im not sure what came on it, well i mean i don't know if it is the stock prop, i was told it has a hell of a whole shot but its December and im tiring to get this all ready by early spring and i willbe doing a lot of river fishing with a pretty strong current and i was wondering if the lower type gear/ prop or does it not matter about the current?

 

[Bifflefan]

Re: buying a new prop new help

All props will make you move, and as long as it has blades and can turn without to much hub slip, it will move the boat faster than the river.

Use the one you have a few times and see how it does. There is no reason to spend money poorly at this point. Wait to see what you have before trying to fix a problem that may not exist.

Read the prop section posts. There is good info in it, and get speed and RPM's with weights. then post that info if you feel it can do better. After that we can give you some good suggestions.

Trying to learn is great, but until you test what you have, you have no starting point.

 

[steelespike]

Re: buying a new prop new help

yea im not sure what came on it, well i mean i don't know if it is the stock prop, i was told it has a hell of a whole shot but its December and im tiring to get this all ready by early spring and i willbe doing a lot of river fishing with a pretty strong current and i was wondering if the lower type gear/ prop or does it not matter about the current?

We still need to know about the boat also Look on the prop for numbers.
Getting the motor propped right is important for the health of the motor and of course
best performance. If the motor revs too high you could have premature failure,
if it lugs, unable to reach max rpm, could cause premature repair problems and sluggish performance.Thus the importance of a tach.

 

[ILMuskieHunter]

Re: buying a new prop new help

Well it going on a 14ft sea nymph river boat

 

[Silvertip]

Re: buying a new prop new help

There is a "sticky" titled "Read This First" a little above your original post. I suggest you read that post to see why we can be of little help. Not only can we not see your boat, we have not idea how the boat performed with the prop you had. To learn about prop pitch, do Yahoo or Google search on "Marine Propeller Theory", "Propeller Pitch" or similar search terms. There is enough info out there to make your eyes bleed. The long and short of prop pitch is that a prop with 12 inches of pitch for example, would propel the boat forward 12 inches with each revolution of the prop. That is theoretical since the prop is working in a liquid and there is some slippage to consider. And no, just because there is 14 inch pitch prop that "fits" your engine, does not mean it is ok to use it if the engine actually requires a "12P". 14P would lug the engine while a 11 would over rev it.

 

[steelespike]

Re: buying a new prop new help

There are 14ft boats that are what I call big or full sized athers are smaller usually less than 14 and somewhat narrower and not as deep.Look up new boats and compare the various models. These smaller 14s are lighter but may struggle more to get a load on plane.Both types are in the range of your 18 assuming the boat is rated for at least 18.
If you typically boat with 2 or 3 others aboard you will likely need less pitch than if its you and a buddy and light gear.If you don't want to check your prop size or see if they can fix it just go with the original brochure size 9 1/4 X 11.You will note that it is closer to the high end which will likely work ok with lighter loads.If you and a buddy add up to 500 lbs I wouldn't call that a light load in a small 14.