rickdb1boat
Supreme Mariner
- Joined
- Jan 23, 2002
- Messages
- 11,195
Re: 88 hp Evinrude SPL prop???
walleyehed + harpjames35 <br /><br />If I might jump in here for a sec. You should be able to turn a cupped 17" prop on a 15' runabout with no problem and at least hit 5500 RPM's and 40 MPH with that motor. Heck, my sis-in-law has a 24' toon with the 88 on it, running a 14" X 13" prop and it hits 5600 RPM's.Something is amiss here. I would try another prop and go with at least a 17" pitch. It Can always be re-pitched to a 15" or 19" if nessesary. Also, for a comparison, I had a 1967 Merc 65 HP turning a 17" pitch prop at 5500 RPM's on a 15" Wellcraft runabout and it hit 37 MPH. So, I would have to assume you would do better with the 88HP on yours. According to the prop selector, you should be running a 14" X 21" pitch for your size boat with a light load. My Wellcraft is a pretty heavy 15'er, hence the 17" pitch on the 65 HP motor. Either your Tach is wrong, the speedo is wrong, the prop pitch is wrong or the motor is not up to snuff. Try to borrow another tach and see what it reads. That's what's important right now. Then you can determine if you are even close to having the correct prop.Any numbers stamped on the hub of the prop you have now?
walleyehed + harpjames35 <br /><br />If I might jump in here for a sec. You should be able to turn a cupped 17" prop on a 15' runabout with no problem and at least hit 5500 RPM's and 40 MPH with that motor. Heck, my sis-in-law has a 24' toon with the 88 on it, running a 14" X 13" prop and it hits 5600 RPM's.Something is amiss here. I would try another prop and go with at least a 17" pitch. It Can always be re-pitched to a 15" or 19" if nessesary. Also, for a comparison, I had a 1967 Merc 65 HP turning a 17" pitch prop at 5500 RPM's on a 15" Wellcraft runabout and it hit 37 MPH. So, I would have to assume you would do better with the 88HP on yours. According to the prop selector, you should be running a 14" X 21" pitch for your size boat with a light load. My Wellcraft is a pretty heavy 15'er, hence the 17" pitch on the 65 HP motor. Either your Tach is wrong, the speedo is wrong, the prop pitch is wrong or the motor is not up to snuff. Try to borrow another tach and see what it reads. That's what's important right now. Then you can determine if you are even close to having the correct prop.Any numbers stamped on the hub of the prop you have now?