96 xp intermittent miss

[furrywolf316]

The xp will start normally and Idle normally but after launch it feels like it drops a cylinder(engine breaks up). I can turn off the engine and refire it and the problem goes away until I take off again. It will run 10-30 seconds before it breaks up but stopping and starting the engine will clear it. After this has happend a few times it will stop acting up and run normally. If you hit the trim button the engine will momentarily pick back up but only for a second. The ski was put up with this problem and sat for 2 seasons unused. I drained the old gas, went through the carbs and replaced the 3 filters. Compression was good on both cylinders too. If anyone has any clue on what is causing this I'd love some help.

Thanks

 

[JoeZ]

Did you pull the plugs yet?

 

[furrywolf316]

I havent pulled them yet but will do that and post back.

Thanks

 

[furrywolf316]

Neither plug looked bad allthough the rear plug was slightly darker then the front one.

 

[JoeZ]

Slightly darker as in overheating, or carbon fouled? Sounds like you might be running lean on that second carb, which would explain it only happening under power, if it were over heating. If carbon fouled, you may have voltage issues and that is creating a rich mixture.

After rereading your initial post, are you saying that it will run fine after a couple restarts and you won't have any problems? This kinda goes more with scenerio two...

Else, you never did mention replacing the spark plugs...have you tried that?

 

[furrywolf316]

It acts like an electrical problem because it will launch great...immediatly drop a cylinder or just start breaking up (I'm not sure which). I can stop and restart the engine and it will launch great and maybe run 10 seconds before it breaks up again. after a few restarts like this it will run fine until after it has set for a while. If you hit the trim button while the engine is acting up it will momentarily smooth out each time you hit the trim button which makes me think its an electrical problem. Neither plug looks carbon fouled and since after about 6 or so restarts it will run fine i doubt its the plugs.

 

[JoeZ]

then yeah I'm inclined to agree it is something electrical, which I suggest you take it to the shop. Before you take it in, you can always check all the grounds and make sure no wires are worn from rubbing. Also, make sure the magneto assembly is clean (ie: no rust) and is functioning properly.

Else, take her in.

 

[furrywolf316]

Ok, thanks for the help