finally got some decent water to open up the new South Bay 520CR with a Evinrude 90 pontoon series. Got up to about 19 mph at 5700 rpm. It was windy and we were in a weedy area. Is that reasonable? I need to buy a spare prop and am wondering if I should stay with the same prop or change it up a bit. Boat and motor plus fuel and two adults weight about 2700 lbs.
Try it again on a nice day and average the readings for 2 back to back runs 180° apart to negate the effects of current and/or wind.
Your 3-cylinder 90 HP Pontoon series outboard has a recommended rpm range of 5000 to 5500. It is best to prop as close as you can to the redline rpm with a light load onboard so as to not lug the motor when you take on a large number of people and gear.
"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.