I'm watching this post to see where it goes
The new Rockets have decompressors. These keep the exhaust valves open before startup to make turnover easier. I suspect that might be the case here. This drove me crazy when I was first checking valve clearances, as some were waaaayyyyy to open. If the cylinder in question is in position for the exhaust valve to be be closed while running, but it is not running, that valve will be propped open and that would give you zero compression.
I am curious as to how much it holds down those exhaust valves Measuring with and without would give us the answer if possible?
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