Prop Question

[duckcrazed]

I Have an underperforming engine (25HP Johnson) on a 15' Duracraft. Top speed w/ no gear is around 25mph....I'd like to increase speed. I currently have a 10 x 13 prop. I was thinking of going with a 10 x 14 or 10 x 15. My question is, Is a 10 x 15 going to be too large a jump? All 3 are recommended for that horsepower engine in various guides....I don't have a tach so I can't see what my current rpm range is.....

[BigBallin]

What knida weight is the boat set up with...Console, elec start, live wells, floors? 25 doesn't really sound off. Do you currently run alum or stainless? If you got an aluminum a stainless of the same size could possibly wake it up a little. If you are already running stainless you might try the next size up with some success but without seeing/hearing the boat run and without a tach its hard to guess. My 15' eagle\25 merc with very little weight (battery, troll mot, a couple of rods and tackle boxes, and 2 fellas runs about 25 +\- 1 or 2 and gains about 2 mph when the big guy gets out.

[Simple Man]

I have a 1548 SeaArk with a 25 Mercury. The prop is a 10x13 stainless steel. It runs 28mph at WOT when I am by myself and it is trimmed just right.

I do have a CMC PT-35 tilt/trim unit and a hydrofoil on the cavitation plate that makes all the difference in the world.

I just don't know how much more speed you could expect to get w/the 25 without losing all of your bottom end.

It'll run about 22mph fully loaded w/a blind on it during the season.

[mrtroy4man]

Do you have a 2cyl or 3cyl 25 johnson25? I have the 25 3cyl(2000 year) with the factory prop, and loaded with gear and 2 fat guys 260lbs me 240 friend, 3 gallons of gas, battery and blind it will run 29 mph, according to my gps. This is with the 3 blade prop. With the 4 blade prop, speed doesn't seem to change on top end, but it has more grunt on the low-end. Good for plowing through stuff. Thi is on a 14 alumacraft. Pretty sure the props are aluminum, not stainless steel.

[duckcrazed]

2 cycle 1995 Johnson...side console...drops down to around 20 mph w/ buddy, dog and blind.....I've done several searches and haven't found stainless props for this model of Johnson......everything appears to be aluminum.....

[CWPINST]

You need more motor. If it is slowing down that much with a moderate load, you will really bog it down with a 15 pitch. The best way to know for sure is to tach it. Bogging down a 2 stroke is the worse thing that you can do to it. You probably need a 40HP.

[Simple Man]

I have a brand new tach - never used - that I'll sell ya...

[DRDUCK]

I got a OMC tach or I will by your MOTOR if the PRICE IS RIGHT> PM if intersted