I have a Honwave 3.8 AE with a Mercury 15HP 2str, some have commented in the past that I perhaps should change the prop to suit the boat, in which case which prop should I purchase to improve performance?
Also, I notice that the engine has an angle adjustment near the transom mounting (setting 1/2/3), which would be optimum?
You need an RPM meter to see what the engine is doing at full throttle, then you need a prop which allows it to achieve somewhere between the minimum and maximum.
For instance my Tohatsu 9.8 has a max recommened RPM of 5-6,000 and with the standard 8.5 pitch prop it achieves 5500.
I tried a 9.5 and it only managed 5 000 rpm at full throttle.
Thanks dude, perhaps I'll just stick with what I have then. It flies with 2 people onboard, with 4 people it feels rather sluggish at low revs but great at higher revs.
>>>It flies with 2 people onboard, with 4 people it feels rather sluggish at low revs but great at higher revs.
I think that's very much what to expect with an inflatable and 15hp. With two (or three if light) a 15hp will pop a sub 4m inflatable on the plane quickly and it feels easy. If you are talking four adult weights the outboard feels a bit bogged down until it pushes the boat to a speed where it's skimming along nicely.
I've always found the standard props on 10/15hp outboards about right for SIB use.
If it's mandatory to go out boating with 4 mates, you need to install an induction tach and check max wot rpm achieved with 4, then you can dial best prop pitch to optimize best top rpm for that combo.
