Rough idle

DARTLARRY said

cylinders are at 125psi, except #1, it is at 110psi. I brought that cylinder up to top dead center, and filled it with 40 psi of compressed air. Air was leaking into the crankcase, I could hear it when I pulled the oil cap. Bad rings on that cylinder?

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It's interesting that one cylinder is 15 psi below the others, and it may indeed be weaker.
But have you tried the same 40 psi air test on one of the other cylinders? Rings are never a 100% perfect seal because they have end gaps, so I'd expect to hear some hissing air, even if a small amount.