So I bought an outboard, and now need help

[HokeySon]

Bought a used ceebee avenger, shallow v river boat. It has a Mercury black max 150 hanging on the transom and a bronson/quicksilver II 20 pitch prop (don't know the diameter). The thing is a dog. It revs up out of the water, but falls on its face if you give it more than a tiny bit of throttle in the water. It will not come out of the hole (has a front tank so I do not get much bow rise either). When you finally get it going and ease into full throttle, it reaches the breck neck speed of 30 mph @ 3000 rpms (at least according to the gauges in it) with a full load of 2 adults 5 kids (so probably 800 lbs -- maybe 850). Tilting up can get me about 500 more rpms until it starts porpoising too much and even those extra R's give me no more speed.
So ... its the wrong prop I assume. The prop does have some dings in it, but never having an outboard before, I do not know if they are serious, they do not look bad to me, just a few small chips out of the leading edges. ANything else it could be? What should I do? thanks.

[STV_Keith]

Call a prop shop. A good one should know the boat design, motor and power, and should be able to make a good recommendation on a prop. I use R & R Prop Shop (http://www.randrpropshop.com) in NV. 702-564-7502.

[eliminatedsprinter]

Most of the avenger's I've seen were around 17 ft and would fly if they had a 150 (most I've seen had 90-115hp and were still faster than that). I think it could be more than just your prop. My boat is 19 ft with an 150 E-rude that is currently having motor problems and it still turns a 21 pitch prop 1900 rpm and 20mph faster than that. When it ran right it got 900 rpms and 10 mph more than it does now....I'd say get both the prop and the motor checked.

[Tom Brown]

Yeah, something's wrong with that BlackMax. I'd get that sorted out before you start playing with props.
I've got a 175 Black Max (2.0 liter) and it pushes my 17.5 foot family boat (around 1200 pound bare hull) to around 50 mph. There's definitely something wrong.
That 3000 RPM number is interesting. Isn't that where the high side of the stator takes over?

[HokeySon]

Guess I will take it in. Anybody know a good shop on the Blythe area? How about River Speed and Sport?

[Ronny]

i owned a 16 ft avenger with a 85 hp. with a average (ski/speed) prop it would go 45-48 with 2-4 adults. my 16.5 avenger with 115 hp would do a little better 48-52. my 18 foot laser with carb 150 max wa good for 75 mph. even with that pull prop you should be way up in speed. seems a compression check in order.

[lucky]

I bought an outboard and i need help..... lmao