I have a 84 200ES with a ignition problem, the unit will run about 2 hrs then will stop, if I pull the plug it will have a very weak spark. I can clean and regap the plug and the unit still will not start. If I replace the plug with a new one the unit will start right up. Additionally the unit tends to backfire at higher RPM's.
I have replace the CDI box, the ignition coil, coil wire, spark plug cap, and I have checked all the wires very carefully. In addition I have checked the pick up coil and that test well within specs, and the exciter coil, also well within specs.
This engine has a fresh overhaul (the problem excisted before the overhaul) compression test runs 135PSI.
I have entertained the idea of the rotor losing it's magnatism but, when I had the engine apart it seemed to have a very strong pull.
I already have far more in this unit than it is worth, if anyone has experenced anything like this or has any ideas I would appreciate it.

Thanks,

Madd Mongo

 

rebiuld carb i have a 200es that did the same thing. all i did was replace the slide needle and the brass guide it rides in and that took care of the problem. the needle may look fine but being brass the wear is not visible you will have to carefully use a punck from the top side of the carb to knock out the guide. it will cost you about $40.00 for those parts ,but wlile you have it apart you should go ahead a rebuild it.