Working on a ltttle Chinook today. No spark on the left cylinder so pulled it apart to file points. This can be done sneeking through the flywheel. There are two sets of points, top set is for the left cylinder and bottom set for the right cylinder. Works best to use folded 400 grit sandpaper then fold a dollar bill several times to give it the final buffing. This seems to work the best, I supose a 100 dollar bill would work better as they are usually stiffer. Got her to run pretty good but is still getting just a little too much fuel. Supose I will have to take the carb apart and investagate.
Joe