25 HP Evinrude/14' Lund Prop Questions

[Eelpout08]

Looking to get a new or used prop for my '82 25hp evinrude tiller, the current one that was on it when i bought the boat is pretty chewed up. Currently i have a 9.2x12 prop and i am wondering if i should look for one the same size and pitch or if i should go up or down? is there a good guideline for picking a prop or is it just trial and error? the boat performs ok now but that is with the prop being dinged and mashed on the ends of the blades. not sure how much it will change with a fresh one.

Need your expert opinions!

The boat is a 1992 aluminum 14 ft lund with 3 benches, front and rear casting decks added and a deep cycle battery with bow mount trolling motor in front. so far the only time i have trouble getting on plane is with me in the back driving (150 lbs) and another guy in the very front (185 lbs?). if i have him move to the middle it is like night and day.

Thanks for helping!

[Jim Almquist]

A new prop will help if it is as chewed up as you have described. You could also take a look to see if you boat motor is set to trim in all the way for more of a hole shot. When your motor drops down it sits on a pin that can be moved so if it is moved out you get more top end and less hole shoe and that sort of sounds like what is happening right now.

[hydro]

A 12" prop is on the high side for the boat and load you describe. An 11" pitch would probably get the boat out of the water better and carry more load. Your description of having to move the passenger to plane is the clue here.

[mnmarlin]

I have a similar boat (87 Lund S-16 DLX with a floor, and an added bow casting deck) and same motor 86 25 hp Evinrude and run a 10 x 13 prop. The motor has been run HARD, and has low compression (110 lbs) but it will easily plane the boat with 3 people in it, and will actually plane with 4 big adults in it reasonably well. I have two batteries in the boat also. I would make sure the motor is running as well as it can (is it running on both cylinders all the time?) before changing the prop unless the prop is really bad.

[brrrr]

I have a s-16 with a 98 yamaha 25 hp 2storke for comparison, I went to a 12 pitch prop and it was too steep unless it was just me in the boat, I went back to my 10.5 pitch and easily can get up on plane with 3-4 people in the boat, even when I max out the weight capaicty of the boat on trout lake or voyager trips the 10.5 has enough to manage. I would look at an 11 also if you are doing pretty well with the 12, you will notice a big difference.

[Eelpout08]

Thanks for all the replies! The motor is running very well so i dont think there is much

to gain there. I will definitly be keeping an eye open for an 11 to try that out, what would everyone recomend for a tach to check the top end RPM?

[deadeye]

You can use a timing light with a display to check the rpms. Otherwise if you want a more permanwnt solution you could get a tach from a auto parts store. Some of them are even a inductive pick up so you don't have to really do and hard wiring.