Prop ?

[Rivernut]

I posted this earlier, but no response. I figured I would try one more time. Does anyone know if I replace my current prop with one with a different pitch, would it have any negative affect on my motor or it's performance! Thx.

[delcecchi]

It might have a negative effect, it might have a positive effect. If the pitch you have now is optimimum then it will be negative. If you are overpropped or underpropped it will be positive.

How do you feel about your current prop's performance?

[delmuts]

it is kind of hard ; if you have a tach , are you getting close to the max RPMs out of it when running flat out? or , no tach. does it sound like you are getting the most out of the engine. if it seems really loaded , then maybe going to less pitch mite be a good move. the best advice i can give , is to talk to a dealer about your rig, how you use it, and they should will be in a better postion to tell you if what you had was a good prop for you , or if some thing different mite be better.

[Rivernut]

The prop I have now needs to be replaced, and I know they offer a couple of different pitch choices. I am also thinking about a 4 blader. I wondered if it could be harder on the motor? Thanks for the input guy's.

[Surface Tension]

We can't help if your not going to give up more information. Whats your max RPMs at WOT? What outboard do you have? Is there some reason why you think you need a different prop. Yes we all know you can get a different pitch prop but without a starting point we're blind here.

[Rivernut]

Easy bud don't jump down my throat!!!!! It's a 25 Merc. The prop I have now is pretty beat up. I'm trying to figure out if I went to a different pitch, if I can get a little more power!

[Valv]

Nobody is jumping at your throat (yet), but we cannot understand what you are asking for unless you specify more details.

If I ask you "my car doesn't run right, can you fix it" what would you say ? Same questions S.T. asked.

We are here to try to help you, but if you get "cranky", nobody will

Back to the main issue, you have a 25hp, what kind of "performance" do you want to get ? It ain't going much faster and cannot pull any skier. If you have to rebuild a prop you can go 1 pitch up and get more speed or 1 pitch down and have more pull, either way it's not going to be too much due to motor size.

I would just replace prop with same size and call it good.

[Surface Tension]

A 25 hp, now were getting somewhere but I have more questions. What size make and model boat? Look at the prop, you should see, dia X pitch, what do you have now.

You say you want more power. Dropping down in pitch will give you more power but you'll get higher RPMs at WOT and your speed will drop.

Weight distribution will have the greatest effect on a rig with a 25 hp. Moving the weight around can make the difference of getting out of the hole and planing out or plowing water. For example, if you have a battery and gas tank in the stern, moving it forward will make a world of difference.

[Northlander]

Or get a stabilzer fin. They will help you get on plane faster and give you better control. Im with Val, on a 25 horse you wont get much out of playing with props. ST has it down as far as weight displacement. Try that 1st then a fin. If that dont work its probably time for a bigger motor. What size boat anyways and what year and make?

[john.wells]

The factory prop is designed for optimal wide range performance. If you get into propping your outboard without proper condsideration of all of the variables as everyone so far has mentioned you could wind up with poorer performance, or worse, catastrophic results. Four or more blades doesn't do much more than smooth out the "drive". In theory, a single blade is the most efficient, but it would shake the ouboard off the transom. Best advice: get the model and serial numbers off of your outboard and bring your prop to a reputable dealer and get what it calls for. If your old prop isn't terribly beat up, you could have it re-worked.

[Rivernut]

Thanks for the 411 guys. Did'nt mean to get a little owly. Nothing meant by it. I guess I'll go W/the factory pitch. It's a 16 foot 600lbs. I would rather get a used 40 but they are few and far between. New is way too much. Thanks again!

[DTro]

I did a lot of research on the same item for my 25hp (disappointed with performance). I found that it made a huge difference with the motor height in regards to the keel.

Make sure the anti-cavitation plate (the fin) is approx even with the keel (not above or below),doing this when the motor at the lowest position. From there you can experiment with the different position settings. My transom was quite a bit short so I had to raise the motor at the brackets so the plate was even at the keel. Made a huge difference.

[Rivernut]

Cool, I'll check into that. My rig performs well, I just thought that since I had to replace the prop, I might check into the pitch? Thank again.

[PerchJerker]

I'd agree with dtro, having motors mounted too low is fairly common on smaller boats. And as others have said, there's only so much (or not much) you can do to improve performance from a smaller motor like a 25 hp. General rule of thumb is you need to be over 60 hp to start to see benefits from playing around with prop pitch and design.

[Rivernut]

Thank, thats kind of what I thought. Thanks for the input EVERYONE!!!