I’m not sure as to why the Tiny Tach is reading so differently between cylinders. I don’t know exactly how they work. However, I have two thoughts to offer: First, I have a KV meter that works inductively, off the spark plug wires, like the Tiny Tach does. I get low KV when the cylinder is too rich, high KV when it is lean and in the middle when it is running as it should. Could this variation be causing the strange readings in RPM, on a Tiny Tach? Second, I have seen broken reed valves on those 32 cube OMCs, a few times. More often than any other model engine, that’s for sure. Some say to hold a piece of card board in front of the carb and see if you get fuel spitting back onto the card board; but I have found that test to be misleading. They spit back some, even when they’re working right. If I had that engine, I’d be at least taking a physical look at the reed valves, to rule them out, if nothing else. As a final thought, you mention that the spark jumps a 1/4″. Those ignitions should fire 3/8″ with no problems. I believe that is the factory-recommended gap for spark testing.
Long live American manufacturing!
