directmule
Member
This is what I have, 2006 Yamaha F150 4 stroke Manual say’s 5000-6000rpm Full Throttle Operating Range (Maximum Output 150hp @ 5500rpm) I like the 5500 figure better than the 6 grand one, we’re talking a 4 stroke outboard here not an indy car.
When we first got the boat in 2008 it would hit 5100rpm but since then and adding two large #31 AGM batteries, trim tabs, huge wash down pump, s/s arch, radar, pot/anchor puller, anchor, chain & rope, guest charger, etc etc it will only hit 4600/4700rpm trimmed out.
I have a 14 x 19p Quicksilver #2016P19 3 blade aluminum prop, thinking of keeping this one for a spare and going to a 4 blade s/s (I like shiny things)
From what I understand, every 1” in pitch change is around 150 – 200rpm change roughly, going both ways, either up or down depending on which way you go, in my case it would be down. So if I can only hit 4700rpm and want to hit 5500rpm I would theoretically go to a 15” pitch but when you go to a 4 blade s/s you don’t need to go that much of a drop. Question is should I go with a 16” / 17”, still staying with the 14 or 14.25 dia. Not looking for top end speed, looking for good cruising/fuel economy speed.
Next question, boat now, as loaded, does 25mph at 3300/3400rpm and fuel meter say’s 5.8/6gph and if I keep track of mileage and fill it up, it’s pretty damn close to it’s figure. What is this different prop going to do to those figures?
Dennis
When we first got the boat in 2008 it would hit 5100rpm but since then and adding two large #31 AGM batteries, trim tabs, huge wash down pump, s/s arch, radar, pot/anchor puller, anchor, chain & rope, guest charger, etc etc it will only hit 4600/4700rpm trimmed out.
I have a 14 x 19p Quicksilver #2016P19 3 blade aluminum prop, thinking of keeping this one for a spare and going to a 4 blade s/s (I like shiny things)
From what I understand, every 1” in pitch change is around 150 – 200rpm change roughly, going both ways, either up or down depending on which way you go, in my case it would be down. So if I can only hit 4700rpm and want to hit 5500rpm I would theoretically go to a 15” pitch but when you go to a 4 blade s/s you don’t need to go that much of a drop. Question is should I go with a 16” / 17”, still staying with the 14 or 14.25 dia. Not looking for top end speed, looking for good cruising/fuel economy speed.
Next question, boat now, as loaded, does 25mph at 3300/3400rpm and fuel meter say’s 5.8/6gph and if I keep track of mileage and fill it up, it’s pretty damn close to it’s figure. What is this different prop going to do to those figures?
Dennis