i have a 2002 4 stroke yamaha .how can i get more speed out of it .can i go from a 9 1/4 x 10 1/2 aluminum prop to a 9 1/4 x 11 pitch prop.will it have enough rpms.this is my first 4 stroke and it does not seam to push boat as fast as my 1989 evinrude 2 stroke.any help would be great on more hp...
i have a 2002 f-15 4-stroke i bought used and was told it ran fine.it cools good when it is hooked to the water hose at the top of motor where the water hose connection is.but when it is in the water it pumps ok at idle but starts to get vary hot on the spark plug side.also stops pumping at...