I have a 1989 40 HP> evinrude. Has been running fine but in big waves water went down vent tube and entered tank and contaminated fuel. I drained the onboard tank and flushed out lines. The motor runs fine at wot but when trolling at 1000 rpms it will spit and sputter and makes it difficult to troll. I also changed the fuel filter and plugs. Any suggestions would be appreciated.
