The standard factory warranty is 3 years of coverage unless it is used commercially, then it is one year. There have been sales incentives that extended coverage up to 5 years.
You will have to have the motor transferred to your name and if it is over 3 years old(or 300 hours) then you will have to show proof of the factory required servicing to activate the addtional 2 years of coverage if that was included.
Call Evinrude support with your serial number and they can look up the warranty situation for your outboard, 262-884-5993
An Evinrude tech will have to isnpect your engine by checking for any air or restrictions in the fuel system and monitor the output pressures of the lift pump and electric pump at all speeds to determine if it is a fuel delivery problem. Since you purchased this rig used, also have the tech do a complete inspection on the motor to make sure everything is adjusted correctly, that it has the right prop on it, and to determine if the motor is in good health.
"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.