I just bought a used 2006 BF150 to go on my Aquasport 215DC. The boat weights 3000 lbs dry. It did not come with a prop and I am trying to figure out which one to order??
Glad you got back to the forum and shared the results!
As indicated, "that is a lot of boat for a 150." Your set up look like that prop is sized perfect; reaching 5900 at WOT.
What prop is it? Manufacturer and material. You may be able to improve a slight bit, but HP will be what gets you where you want.
Assuming your drive is adjustable, what height is the anti-valant plate (it is just above the prop). It should be even to around 1" above the bottom of the hull. Use a long straight edge and measure from along the flat of the hull.
Still thinking you need another 100 HP to get you everything you want..
Glad you got back to the forum and shared the results!
As indicated, "that is a lot of boat for a 150." Your set up look like that prop is sized perfect; reaching 5900 at WOT.
What prop is it? Manufacturer and material. You may be able to improve a slight bit, but HP will be what gets you where you want.
Assuming your drive is adjustable, what height is the anti-valant plate (it is just above the prop). It should be even to around 1" above the bottom of the hull. Use a long straight edge and measure from along the flat of the hull.
Still thinking you need another 100 HP to get you everything you want..
It's a Honda Aluminum Prop. And Yes the anti-valant plate is about 1" above the bottom.
I ran the numbers for prop slip and i'm around 35-40% which is really high. The engine revs very easily. If i punch it, it climes to 5900 rpm fast but the boat is slow to move. Same is true when conditions are choppy. I have to increase rmps to maintain speed.
It's a Honda Aluminum Prop. And Yes the anti-valant plate is about 1" above the bottom.
I ran the numbers for prop slip and i'm around 35-40% which is really high. The engine revs very easily. If i punch it, it climes to 5900 rpm fast but the boat is slow to move. Same is true when conditions are choppy. I have to increase rmps to maintain speed.
Yes, that slip is quite high. In many cases, changing to a SS prop greatly reduces slip, so rpm can drop while hole-shot and top speed improve.
You may want to consider a 4-blade SS.... you will get on plane faster and be able to hold it at lower speeds. A typical drop in rpm from a 3 to a 4 blade requires a 1" pitch drop to compensate. Going from that much slip on a 3 blade AL to a 4-blade SS may require a 2" pitch drop.
I also ran the numbers, 33 knots/38mph,2.14 ratio, 5900 rpm wot, slip is about 15% which is not unreasonable for a heavy boat/smaller motor.
Sounds like you are having some ventilation issues if the motor revs up that fast or looses grip in a seaway. Are you trimmed up high when this happens? The ventilation plate 1" above seems reasonable though.
I also ran the numbers, 33 knots/38mph,2.14 ratio, 5900 rpm wot, slip is about 15% which is not unreasonable for a heavy boat/smaller motor.
Sounds like you are having some ventilation issues if the motor revs up that fast or looses grip in a seaway. Are you trimmed up high when this happens? The ventilation plate 1" above seems reasonable though.
No I'm not trimmed up. I used a online prop slip calculator, I input knots and i'm sure it was assuming mph. So i guess it's not as bad as I thought. But that doesn't fix my issue.
I would like a little better hole shot, better response when I increase rmps, and a lower rpms (44-4500 would be nice) at cruising speed (20knts). I don't care about top speed too much.
Some other info that might help.. Before I installed this Honda 150 I had a Suzuki 225hp 2 stroke. It has issues, low compression, ect before locking up... But the boat felt good. It had a 2.29 ratio and a 14x20 stainless prop. I can't remember any of the rpms. It never revved fast like this motor does.
Looking at the specs for the motor (http://marine.honda.com/Products/modeldetail/BF150), confirmed 6000 is max rated rpm. The slip of 15% is not bad and will only slightly improve with a prop change. I should have looked up the specs on the gear ratio before assuming the 30% slip was accurate.
Now, knowing you had a 225 HP motor before and that it performed as you wanted it, that 75 HP difference is huge.... sorry to state the obvious. I would say it's time to sell the BF150 and upgrade back to a 225, or even a 250; not to exceed the boat max rated HP.
Don't think you will get the performance you want with the engine/boat you're using.
