If you have run the engine with the stuck valve it has most likely damaged the engine anyway. (broke guide, bent valve or hole in piston) If you really want to check it with out tearing down the engine at least pull it and then pull the spark plugs and manifolds, both intake and exhaust. Then get in there with a bright light and look over
all the valves, their guides... get the light positioned so you can see down through the spark plug hole to see the top of the piston... look at where the exhaust everything valve has been hitting the piston... it has to have left a mark of some sort. This should at least tell you if the valve has been moving back up enough to keep from doing damage. And since you have it this far rip that head off anyway and fix the problem right by unsticking the valve. You will be much happier after it's back together again and all the valves working correctly. I have seen the results of a dropped or stuck valve at around 4000 to 4500 rpm... it's not pretty you only end up with one good head and a few large chunks of alumunim. Olspeed
66 Ghia, "Dexter" 76 flat window Beetle
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