If yours goes only one way, the circuit to the other side is plugged up with sealer or your switching linkage is on wrong. Just get some thin gasket material and cut your own gaskets. Use the blunt end of small drill bits to punch holes and a sharp knife to cut the gasket. Works best if you have a old one to start with. If not, go to the e-bay link and get a set. Sealer is not what you want to use. Also, make sure the linkage is switching directions, the small spring must be in place. Trico used a lot of the same parts on different motors, so look for cores that look about the same if you need a small part.
The switching mechanisim should click as the paddle reaches the ends of it stroke, the spring pulls it each way creating the clicking sound when the motors are running. It will never run if the linkage isn't free.
