I Just purchased a 89 maxum 17ft with a 85 hp force o/b motor.At max throttle it runs at 3900-to 4000 RPM.Is this the area it should be in, or should it be in the 5000 range.If so How do I fix this problem?
Ahoy, Medic. On the front of the prop (you have to remove it) should be numbers like 13-1/4X17. Which tell the prop diameter and pitch. The pitch is how many inches the prop would advance through the water in one full revolution if there were zero slip. Changing prop pitch works like changing gear ratios in a car or bike. We are assuming that your engine is in proper tune but you have the wrong pitch prop (too long). By replacing it with one with an inch or two shorter pitch we expect that you will improve accelleration and allow the engine to reach its designed operating range of rpm, around 5500rpm.<br /><br />Standing by,<br />Red sky at night. . .<br />JB
