the pto side piston is not doing anything to help the engine run right now. i can take the plug cap off the sparkplug and the revs dont change at all. i fired it up with the sparkplug in the boot, sitting on the head and i still have a good blue spark. i tried switching the middle and pto side plug boots and still the pto side does nothing. i even tried switching the middle and pto side carbs, but when i pull the boot off the pto side plug, the revs stay the same! to me this sounds like something is wrong with either the pto crankshaft seal or its just time to rebuild a tired engine. im going to pick up some ether or starting fluid to spray around that seal to see if it does anything. the carb boots are weather checked, but they are not through. the compression is about 110-115 on each cylinder, but the middle and stator side still work. any ideas on what the problem could be, or what i chould check next?