Chainsaw Repair

I have one of the 50cc Echo clamshell engines set up as a model airplane engine. They run as well as a Sachs-Dolmar or Mahle cylinder closed port engine. There are a couple people in the area besides me that have these set up as model airplane engines. The spark plug is a NGK BPMR6F tapered seat spark plug which is much smaller on the outside as a 7A plug. The plug is the same on the inside and fits the hole perfect without modification.

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