Changed Lower seals tonight. Did everything very carefully. Noiticed when I was adjusting valves I would here a "hop" when rotating engine over 180 degrees. Re-did the whole thing , same thing. Finally found exhaust valves on #3 and #4 cylinder ( the 2 closest to each other) seem to stick and then "Pop" loose. Finally decided to put it together and see if I started it if it would clear up. Cranked it up and it sounded great for about 45 seconds, them a couple of pops, them a few more so I shut it down. Waited a few minutes and the same thing happend. Cranked it again and increased the revs and it went away, but as it decreased revs it sounded very bad. Any ideas???? No noise at all before I took it down and I noticed it when I was reseting the valves.....I had not started it yet.

Any help would be great!!!

 

Someone said to try "Sea Foam" in the engine. Ran one bottle through and the problem got 50% better. Going to try another with the engine hot. Was told that the valves get a "varnish" on them and it may have rubbed off and caused the valve to stick in the guide.