skydiveD30571
Lieutenant Junior Grade
- Joined
- Feb 13, 2012
- Messages
- 1,042
1) Performance issue you are trying to correct.
Would like greater hole shot, so I'm interested in a 4 blade SS, but curious about over-revving (see below)
2) Current prop manufacturer, model, aluminum or stainless as a minimum.
Michigan Wheel Apollo stainless steel 3 blade
3) Current prop diameter and pitch (required).
14.25 x 19
4) Wide open throttle RPM and speed with an average load (very helpful)
4600rpm trimmed with smooth water and just me on board. With a normal load of a 4 people, about 4200rpm. Speed is a little over 50mph with just me, in the upper 40's with normal load.
5) Engine/drive make, model, year, and HP
2006 Volo Penta 5.0GL-H 220HP with sx-a 1.60 drive
6) Boat make model, year, length and weight
2007 Seaswirl 210 BR. 21ft, aprox. 3000lb dry.
I originally had a 3 blade aluminum prop that was pitched 21" when I bought the boat last year. I noticed right away it struggled hitting 4000rpm so I replaced it with the Apollo SS 19" pitch and it was much better. Last year it would hit near 4800rpm with a light load, and about 4500 with a normal load. Over the winter, the boat got heavier with the addition of a wakeboard tower and extra electronics. The prop is also dull and slightly burred up from running aground on a sandbar with small rocks. This year it barely reaches 4600rpm, and with a normal load is around 4200rpm. Volvo suggests 4400-4800.
The question is, I know a new clean sharp prop will have more efficiency and pick up some of that lost rpm, but I'm not sure how much. I dont really care about top end speed since I hate burning a tank of gas in a few hours. We wakeboard alot so holeshot is more important to me. I know that when going to a 4 blade prop, they are usually pitched 1" less to account for the added drag. My question is, am I close enough to the suggested rpm range to just go with the 18" 4 blade and hope replacing the dull burred prop puts me in the rpm range, or should I drop 2 more inches of pitch and go for a 16"? I can't seem to find props that change pitch in 1" intervals. I'm afraid dropping 2" will put me slightly over-revving the engine. As always, any input is appreciated!
Would like greater hole shot, so I'm interested in a 4 blade SS, but curious about over-revving (see below)
2) Current prop manufacturer, model, aluminum or stainless as a minimum.
Michigan Wheel Apollo stainless steel 3 blade
3) Current prop diameter and pitch (required).
14.25 x 19
4) Wide open throttle RPM and speed with an average load (very helpful)
4600rpm trimmed with smooth water and just me on board. With a normal load of a 4 people, about 4200rpm. Speed is a little over 50mph with just me, in the upper 40's with normal load.
5) Engine/drive make, model, year, and HP
2006 Volo Penta 5.0GL-H 220HP with sx-a 1.60 drive
6) Boat make model, year, length and weight
2007 Seaswirl 210 BR. 21ft, aprox. 3000lb dry.
I originally had a 3 blade aluminum prop that was pitched 21" when I bought the boat last year. I noticed right away it struggled hitting 4000rpm so I replaced it with the Apollo SS 19" pitch and it was much better. Last year it would hit near 4800rpm with a light load, and about 4500 with a normal load. Over the winter, the boat got heavier with the addition of a wakeboard tower and extra electronics. The prop is also dull and slightly burred up from running aground on a sandbar with small rocks. This year it barely reaches 4600rpm, and with a normal load is around 4200rpm. Volvo suggests 4400-4800.
The question is, I know a new clean sharp prop will have more efficiency and pick up some of that lost rpm, but I'm not sure how much. I dont really care about top end speed since I hate burning a tank of gas in a few hours. We wakeboard alot so holeshot is more important to me. I know that when going to a 4 blade prop, they are usually pitched 1" less to account for the added drag. My question is, am I close enough to the suggested rpm range to just go with the 18" 4 blade and hope replacing the dull burred prop puts me in the rpm range, or should I drop 2 more inches of pitch and go for a 16"? I can't seem to find props that change pitch in 1" intervals. I'm afraid dropping 2" will put me slightly over-revving the engine. As always, any input is appreciated!
there's no play in it, but when turning it with my hand I can see it kind of doing a small orbit motion where the shaft enters the seal. If its not one thing...