correct prop for boat?

[zildjian29]

I have a 1985 stingray 17ft open bow. Powered by mercruiser 3.0 140hp. Has 13pitch prop now and its not right! Anybody happen to know what pitch is best? 17 or 19 maybe?

 

[SkiDad]

Re: correct prop for boat?

i would start with a 19.... it's probably your best guess.

 

[jestor68]

Re: correct prop for boat?

Take another look and provide the diameter and pitch; It's stamped on the prop hub; something like 15 X 18, for example.

A 13 pitch wouldn't make any sense for that boat.

 

[zildjian29]

Re: correct prop for boat?

14 1/2 x13p.

 

[steelespike]

Re: correct prop for boat?

I agree the 13" is the wrong prop but how does it do with it. Lightly loaded wot rpm and gps speed.
Should over rev easily.
What is the gps speed at 4800 rpm?
Some cell phones have a gps app.
I do agree a 19" is a good starting point.

 

[zildjian29]

Re: correct prop for boat?

Over revs easy and only 20 mph with GPS. Think a 19 is still good for pulling tubs etc.?

 

[SkiDad]

Re: correct prop for boat?

20 mph doesn't sound right even for a 13. I would think more like high 20's. Does the engine run ok. With a 19 I would think 35-40 mph. And tubes are easy to pull

 

[zildjian29]

Re: correct prop for boat?

It could have been low 20s! Engine is great compression in all cylinders is 130. Runs good. I will try a 19 don't think 17 would do it! Thank you. My first inboard always had smaller outboards!