Prop for my deck boat ?

[big_b]

1) Performance issue you are trying to correct.

Seems to need more top end (I only see 28-30 MPH GPS)

2) Current prop manufacturer, model, aluminum or stainless and as a minimum.
I am sure it is aluminum but not sure of manufacturer, It is the stock prop on my 280 outdrive

3) Current prop diameter and pitch (required).
I am not sureof of pitch or diameter(can I just measure to get diamater?) , but it does have the markings on it 533 92
4) Wide open throttle RPM and speed with an average load (very helpful)

I can achieve 5200-5300 RPM easily (above max RPM for this motor) At around 5000 RPM 4 adults, 3 kids, and gear (900 pounds) I can get it up to 28 - 30 MPH (GPS)

5) Engine/drive make, model, year, and HP
1977 Volvo Penta AQ130D (130HP)

6) Boat make model, year, length and weight

1977 Viking Deck Boat (Fiberglass Tri-Hull) 18 feet, Not sure of weight


On a side note, I can pull an adult on a tube with the above 900 pounds aboard easily past 25 MPH (I don't due to safety of course)


It just seems like I should see a little more speed out of this boat.. It planes at right around 17-18 MPH and I can keep on plane after backing down at around 15MPH easily....


My current prop shows wear and has rigged edges all around (from previous owner)

I want to gain top end speed but not lose the ability to tow the tube ..

 

[Bifflefan]

Re: Prop for my deck boat ?

Take that one off and take it in to a prop shop and have them sharpen it up. Also have them measure it so you know what you have. You cant get better until you know what you have to start with.

With the same prop cleaned up and in good condition you should see some increase by that alone.

I want to gain top end speed but not lose the ability to tow the tube ..

You dont get it both ways...

 

[steelespike]

Re: Prop for my deck boat ?

Have you looked under the prop nut for numbers?
You appear to be underpropped but without your prop size and rpm and speed
No way to suggest a number.

 

[big_b]

Re: Prop for my deck boat ?

I looked under the nut but could barely make out the numbers .. I took to Delta Prop in Cleves, OH and they sandblasted it and we found out what it is..

It is made by the Michigan Wheel Company (Or was made) and it is a 14" Diameter with pitch being 15...

The prop shop guy pretty much said that the only prop made that will fit it is actually made by Volvo Penta... I didn;t even think to check this site to see what is offered .. I just did and I see several ..

I ended up buying a 14" diamater with a pitch of 17.. that is all they carried and I didn't want to go to much..

I stayed with aluminum.. I am hoping that the new prop will give me some speed gains ... The prop shop guy said I should see a nice 4-5 MPH increase atleast going from a 15 to a 17 pitch .. Also having a prop that is not all beat up will help too!

Would you guys have chosen a different prop ? I still want to pull tubes just wanted to get the RPM down a little and gain a few MPH ...


What do you guys think I will see in MPH gains ?

Thanks!