prop on 2002 yamaha 4 stroke

[lunkerv16]

I have a 2002 Lund Rebel 1650 SS with a 2002 yamaha 40hp 4 stroke. I am guessing the weight of the boat with two pple and fishing gear to be around 1650 or so. The boat seems very sluggish out of the hole. It runs WOT about 5100 and that is trimmed up just till it starts porposing. It has a 13 pitch prop now. I am thinking either a 11 or 12 pitch would be what i need. I only want to buy one prop so how many rpm can I gain with an 11 or 12p prop? BTW the boat runs about 27 mph with according to my handheld gps. So which one do i need?

 

[lunkerv16]

Re: prop on 2002 yamaha 4 stroke

One more thing, Which brand and style of prop would be best for my setup. I have been looking here on iboats and there is a lot to choose from. Does it make a whole lot of difference or is there one that would suit my needs better? Thanks

 

[steelespike]

Re: prop on 2002 yamaha 4 stroke

Do you have battery(s) and gas tank in the stern?Check that the throttle is opening all the way at the carb.Is the antivent plate ,just above the prop, visable on plane?
In the extreme raising the motor could gain rpm and speed.
You need to be running closer to 6,000.From the seat of the pants I think an 11" pitch. Would get you there.Your present prop seems to be doing the job but for the pitch I would stick with the brand.

 

[lunkerv16]

Re: prop on 2002 yamaha 4 stroke

the gas tank and one battery is in the back of the boat and a bow mount trolling motor and battery is in the bow, the boat feels pretty balanced. The anti cavatation plate is just above the bottom of the hull.

 

[steelespike]

Re: prop on 2002 yamaha 4 stroke

Don't assume that you have full throttle just because a relatively young setup.
Not likely to be a problem but wouldn't be the first one.I've seen brand new setups not reaching full throttle.Antivent plate is probably ok though generally should be visable on plane.Typical setup is about 1" above the bottom but a few end up much farther.

 

[lunkerv16]

Re: prop on 2002 yamaha 4 stroke

I did check the full throttle and that checks out good. I think i am going to go for a solas amita there is one that is 11 3/5" and one that is 11 4/5" diameter. So what difference is there really between the two, they are both 11p props so which one would i want? Thanks

 

[steelespike]

Re: prop on 2002 yamaha 4 stroke

Generally as pitch goes down diameter goes up.
Diameter is a secondary consideration. And I din't think you could tell the difference. I guess if I was picking I would lean to the one closest to your present diameter.