I am new HP rating ?

[uniquebrett]

I am new to this forum, and I am needing a new prop....would like to get a ss one, but before I get there I do not know my hp rating. I do know I have a 1993 VIP 17 foot boat with a 3.0 L engine, mercruiser alpha one out drive. I think my hp is between 120-140 but how do I tell? My current prop is alumimnum probably stock....3 blade with 248P stamped into the side of it between the blades. another # stamped into the prop is 0 3156 . The prop is in worn condtion with metal removed from more than one of the fins. i have another prop for the boat, but the previous owner told me I will have a higher topend but lose pulling power if I use it. we mostly ski an play so I do not want to lose any pulling power. can anyone tell me anything about my set up with what I have provided here?
Thank you
Brett

 

[achris]

Re: I am new HP rating ?

By 1993 all engines were rated by propshaft HP. There is no such thing as a 'stock propeller'. If you need a new one, take the old one off and take it to either a Merc dealer or a dedicated prop shop.... Those numbers don't match anything I recognise.

A genuine Merc prop will have a number like 48-xxxxxA45 17P. The "48-xxxxxA45" is the part number and the 17P is the pitch, in this case 17 inches. If you find numbers like that, then we can find a prop for you....

Chris.........

 

[uniquebrett]

Re: I am new HP rating ?

Thanks for your help and answers....but can anyone tell me hp rating of my motor? I will remove my prop and lood for better #s....are most right handded threads, or left handed threads?...any idea of the weight of my boat?
thanks
Brett

 

[steelespike]

Re: I am new HP rating ?

Thanks for your help and answers....but can anyone tell me hp rating of my motor? I will remove my prop and lood for better #s....are most right handded threads, or left handed threads?...any idea of the weight of my boat?
thanks
Brett

NADA price guide lists it at 135 hp.1900 lbs.
regular righthand threads.

 

[uniquebrett]

Re: I am new HP rating ?

thanks steelespike....very helpful
Brett

 

[uniquebrett]

Re: I am new HP rating ?

I am learning...I got the prop off, and learned it s a14 1/2 inch daimeter with a 17 pitch. The boat at wot 5000rpm is at about 37mph. I am in need of a new prop. any suggestions?
Thank you
Brett

 

[uniquebrett]

Re: I am new HP rating ?

Can I make a suggetion, before spending money on a SS prop, or making changes to pitch, etc.

Have your current prop rebuilt. It will cost $50 - $75 most places, just check your yellow pages. Once that prop is performing properly take note of your speeds at different RPMs, (recording both speed and RPM) including wide open throttle.

Why? Because without some sort of a known good base line you are just guessing and that gets very expensive very quickly.

Bubba - When i got the prop off, a local guy looked at it and stated it is beyond rebuildable. I did observe at last use th boat did this on a performance....wot 5000rpm about 37 mph. this with a chewed up 14.5 ich diameter 17 pitch prop. Any suggestions about a new prop?
Brett

 

[steelespike]

Re: I am new HP rating ?

I am learning...I got the prop off, and learned it s a14 1/2 inch daimeter with a 17 pitch. The boat at wot 5000rpm is at about 37mph. I am in need of a new prop. any suggestions?
Thank you
Brett

Again you can't tell too much with a poor prop.What size is your other prop?
and its condition?Without more concrete figures I wouild stick with a new 17"
pitch.It may be a little light but you can throttle back to keep within range
and it will give you a good hole shot and handle a load better.If you go up in pitch and end up lugging(too low rpm) then you can't use it.When you have the new rpm and speed you can decide better if you need to change props.

 

[uniquebrett]

Re: I am new HP rating ?

Again you can't tell too much with a poor prop.What size is your other prop?
and its condition?Without more concrete figures I wouild stick with a new 17"
pitch.It may be a little light but you can throttle back to keep within range
and it will give you a good hole shot and handle a load better.If you go up in pitch and end up lugging(too low rpm) then you can't use it.When you have the new rpm and speed you can decide better if you need to change props.

Steelespike - My other prop is a 14.5 diameter 19 inch pitch (48-78120-19) L I am assuming the L means counter clockwise rotation....is this correct?

It is in great shape...shoud I try it out and get a wot reading along with speedometer reading...before I buy a 17pitch prop?

Thanks
Brett

 

[Randybeall]

Re: I am new HP rating ?

Yes, try the good 19" prop you have and get back with numbers from its performance. That will give two points of reference even though the first prop was in poor condition. Since your main consideration is hole shot and pulling a 4 blade prop of the correct pitch might be a good idea.

 

[steelespike]

Re: I am new HP rating ?

Usually a prop is marked C for clockwise and CC for counterclockwise.
Easy to tell what it is behind the boat facing the prop c is common cc is not and usually used in twin installations.If you cant figure it out compare to your present prop.CC won't work.