I just finished stripping this trimmer to see the engine. It is quite different than any trimmer engine that I have seen. The carb has no adjustment and two venturies. The top venturi is split in the carb mounting block and goes to a fitting on the front and rear transfer port channels. The bottom venturi feeds a standard cylinder port, but the opening is much smaller. the coompression is good, as are the bearings. It has a two ring piston.

Since I have about 10 engines in my conversion backlog, I don't think that I want to mess with this one. If anyone is interested in trying to make something out of it, you can have it for the shipping cost.