Reply To: Evinrude Fastwin 18 HP 15032 Leaking Around Exhaust

[Don]

Well, it is hard to diagnose just reading your symptoms…Is the engine sneezing and coughing, or actually bucking and kicking…. If it is sneezing and coughing, I’m thinking you have a lean fuel mix for some reason…If it is actually bucking and kicking, then it sounds like ignition to me… Anyway of posting of video of the engine misbehaving? Unfortunately, even the audio qualities of videos can be misleading when diagnosing these issues.
You also mention that the engine is hard to start cold, which nudges me more in the direction of ignition, provided the choke linkage is working correctly. Check to make sure the choke is closing fully and the the butterfly advance is working properly. The choke linkage on these engines is not very positive and doesn’t hold the choke closed very well.
So, I guess it is best to start with the basics…Check compression. Check spark. If spark is OK while cranking, I would try those neon inline spark testers to monitor spark with running/misbehaving…Have you changed the plugs? Just cuz they are new doesn’t mean they are any good. Recheck carb sync, perhaps something is holding the carb butterfly open slightly at idle.