What prop do I have?????

[suzukisam]

Ok this is what my prop says on it: between two blades it says w29 between two others it says 4879574a-4 19p

So I'm assuming that it is a 19 pitch, what other info do I need to order a new prop, obviously the diameter? Does this seems like the right prop for a

1979 seas sprite tri-hull 16"
3.0 GM I/O w140 pre alpha outdrive?

I do not know my WOT, cause I have not had the boat out on the water yet, but this prop is toast.

just a little input would be nice.. thanks

 

[Silvertip]

Re: What prop do I have?????

There are three things you need to know in order to buy a new prop. These three things assume you merely want an exact replacement. It does not guarantee you have the best performing prop for your boat to start with because without some test data (see the READ THIS FIRST sticky at the top of this forum) you simply don't know. So what you need is as follows:

1) Pitch -- you are correct. Your prop is a 19P
2) Material -- Stainless steel or aluminum. (Its either shiny and hard or painted and easily scratched.)
3) Diameter -- If you don't know, measure it. On a three blade you measure from one blade tip to the exact center of the prop shaft and multiply by 2. For a four blade you measure blade tip to blade tip across opposite blades.

Of course there is a fourth factor but that should be obvious. You need to know the make, year and model of your outdrive. The prop needs to fit the drive. There are a gazillion 19P props out there but most of them won't fit your drive. Only those designed for it will fit. Application charts tell you what you need.

 

[suzukisam]

Re: What prop do I have?????

ok obviously It's a new boat(new to me, but old) so I have no test data, and I read the sticky. I guess what I'm trying to find out is does a 19 seem like a good pitch for the boat I listed and I plan to pleasure cruise and ski. I know without having some data and all it's hard to know. I'm planning on running a couple different props and I don't mind spending this summer seeing what really works well with the boat, I just want to make sure this does not seem out of the ball park or anything? I was hopiong someone with a similiar set up could tell me if what I have would be a good place to start since I'm replacing it anyway? lso should I go three or four blade?

 

[steelespike]

Re: What prop do I have?????

My guess is a 19 may be a little light but as a starting point I think your better off with a slightly low pitch.If it turns out it over revs you can still use it just avoid over reving.You can run wot long enough to get the specs you need.

 

[suzukisam]

Re: What prop do I have?????

ok what pitch would you recomend? and what about a 4 blade