I have intermittent problem with #2 cylinder not working. The bottom cylinder plug is completly black and the other three look really good. I have been fighting an ignition problem but now I have good spark 7/16 jump test on all cylinders. The compression is 120,120,118, 118. I put on a different timer base and replaced one of the power packs during the period of ignition problems. I have cleaned the carbs twice soaked, kits, compressed air used to blow out all passages. I'm thinking bottom main seal but I don't know how to check to see if it is leaking. Any help is desparatly needed. Thanks
