I've done a search for this, but couldn't find a conclusive answer. First a little background. I was given a 93 850, that wouldn't start. After new plugs, draining the oil that was about two quarts overfilled, cleaning the flame trap, and putting a new oil filler cap on, I got it to start. It was obvious that something wasn't quite right, so I did a compression check. All cylnders were around 185 except #1 which was zero (this was cold). So I thought maybe it was a stuck lifter or carbon build up on the valve stem and took it out for a sustained high-rpm run. Now I get about 40 lbs. on #1. So my questions is, does this sound like a burned or partially burned valve or will more aggressive high-rpm and maybe some kind of engine flush cure it? I don't think the engine is really worth tearing into because it shows 298,000 on the odometer. It does run pretty well when you get the rpms up though, just a little shaky at idle. What do you think? Is a burmned valve always zero compression or does anything less than normal compression indicate a valve problem?