Pitch question

[Chumdog]

Just bought a 2002 17 ft Nitro. Currently has a Mercury 115 with a ss 21 pitch prop. Boat will not plane at all and just plows through water at extremely slow speed. The guy I bought it from said the motor installer told him to replace the 21 with a 19 for faster speed or a 17 to get on place faster. does this sound right? I should note that I am new to this and have limited knowledge. Be patient if I cannot answer all questions. Thanks for your help.

 

[jimmbo]

Re: Pitch question

Welcome to iboats

When you say the boat won't plane, mushing along at extremely low speed, does the engine rev up or does it too stay at low speed? What exactly is "extremely slow"? Going to a 19 0r 17 would lighten the load on the engine. However, if the engine isn't running properly that is not the solution. Check for obvious things too. Boat overloaded, poor weight ditribution, engine up to snuff, ensure the throttle valves are opening fully when throttle lever is moved.

 

[Chumdog]

Re: Pitch question

Engine is revving fine. Sounds real good. I also think the motor may be mounted a little too low. It feels like a pontoon boat with a 40 HP motor. Back end wont come out at all. I will check the throttle.

 

[steelespike]

Re: Pitch question

Something isn't right.
Was this test run with a light load?
The 21 is probably too much prop but it should plane and give you a base line to work with.
Do you trim down for hole shot?
These motors typically end up with a 19" or 17" pitch you have a relatively small boat I would think a 19 would work easily.

 

[Chumdog]

Re: Pitch question

Load was two adults and 3/4 tank gas (30 gallon capacity). I havent loaded gear yet. I am trimmed down at hole shot. I looked a little closer before I trailered it and, like I said, the motor looked way low in the water when trimmed down all the way. The guy I got it from was up front about this and he said the guy that installed it said the prop was too much. He recommended the 17 or 19. All I have ever owned is a bowrider and pontoon so this is new to me with a bass boat. Guess I will have to do a little trial and error on these props.

 

[steelespike]

Re: Pitch question

Is Nitro a brand or model I could only find info for about 3 years in the 1980s.Found Nitro under Tracker 1000 to about 1300 lbs.
Something isn't right if it won't plane.Nitro sounds like a light fast boat.
Was this test run with a light load?
Perhaps a plug wire is off or the throttle not opening all the way.
The 21 is probably too much prop but it should plane and give you a base line to work with,
we need the wot rpm and gps speed lightly loaded.
Do you trim down for hole shot?
These motors typically end up with about 17" pitch you have a relatively small boat so possibly more.

 

[Chumdog]

Re: Pitch question

Nitro is a Tracker brand by Bass Pro Shop. It has a 1350 lb. dry weight. I will get out and get some more specifics and follow up. I have a local Mercury mechanic and I think he is giving me a 17 and 19 to test. Ill do this and follow up.