just purchased a 2017 90 evinrude e tec for my 1980 boston whaler montauk. I noticed you do a lot of repowers with boston whalers and evinrudes, i have a question on what size prop would be a good starting point. I use it for skiing and tubing and cruising around . i know there are a lot of factors on choosing the right prop , but if could steer me in the right direction it would be helpful ( 3 blade vs 4 blade , stainlees or alum etc.) Thanks for you time Jason
Are you installing a 3 cylinder 90 HP or the V-4 90 HO model?
If it is the 3 cylinder version you will probably want to start with a 17" pitch prop and note the full throttle rpm with the fuel topped off and a normal load of people and gear. For water skiing you want a prop that allows the motor to run near the top of its recommended rpm range.
This link is for a free propeller guide that contains more detail about props and propping.
Propeller Selection Guide Book - #766315
"There is never just one thing wrong with a boat";
-- Travis McGee, main character in a book series by John D. McDonald
The factory recommends that a properly trained technician service your Johnson or Evinrude outboard motor. Should you elect to perform repairs yourself, use caution, common sense, and observe safety procedures in the vicinity of flammable liquids, around moving parts, near high-temperature components, and working with electrical or ignition systems.
The information offered here is only general in nature and should not be construed as complete factory approved procedures, techniques, or specifications. Always use the proper service manual for your motor, up-to-date service literature, the correct tools, and have an understanding of how to proceed with troubleshooting and repair methods. If you are unsure or uncomfortable with a procedure, a situation, or a technique, enlist the services of a factory trained technician.