Hi Guys,
I recently acquired a Fuji 19S (pics attached.) It looks old but fired up the first time and great compression. However its muffler is a bit wierd!!!

First of all, the muffler open in the front and back. I can see through it. Is this normal????

Secondly, its got a flap on the side of the muffler for god knows what!!! My guess is to increase power or is it????

While the engine runs fine, its does not suck in fuel when i flip the prop over with my finger on the air intake but once it starts the fuel flow is cool. Also it only runs straight i.e. stops on nose up or down. Suggests no back pressure from the muffler???

I know its an old engine but its got great compression and being a recent convert to fuel engines, i am keen to learn the ropes before i go to bigger and better things!!!

P.S: I also have an OS MAx 20 which runs OK on my 20 size trainer. but i can feel this Fuji engine has much more power and am keen to replace the older OS max with this old Fuji!!!

Any thoughts?