1994 Evinrude 200 - Just started surging under load
1994 Evinrude 200 E200CXER on 21' Paramount-copy center console. I installed this engine about a month ago. It ran fine when I water tested for 15 minutes on previous owners boat. I have taken it to the lake twice on my boat and engine ran fine for about 15 - 20 minutes each trip. Will run over 6000 rpm when fully trimmed but I have not stretched it out past that. 15 to 20 psi water pressure.
Today it ran fine for first 10 minutes. Then it started surging - if I was running 5500 RPM it would drop to about 5000 for a second, then back up. From a dead stop it would accelerate fine for a few seconds - then fall off - then continue to accelerate but only get up to ~5500. Then surge faster and slower. This behavior continued for 5 -10 minutes at almost any speed until I put on the trailer.
Before I ran it for the first time on my boat, I replaced spin-on water separating fuel filter, fuel line from tank to engine & primer bulb. It has VRO system. The VRO warning buzzer sounded when I first connected the oil tank, but has not sounded since the oil line was primed before first water test. My old `98 225 did not have VRO, so there is 50:1 oil in the fuel tank. I have read somewhere that this is recommended when troubleshooting VRO system to prevent burning up the engine.
Good compression on all cylinders - about 110 psi.
Previous owner had this done in July:epoxy 1 loose magnet back on flywheel, replace timer base, replace stator, replace power pack, replace plug wires.
I have read several posts on several forums and replies seem evenly split between fuel and electrical. Maybe my particular symptoms will jog someones memory.
Thanks in advance!
