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Re: Old-school running compression test help needed
Posted to Technical Discussion Forum on 3/10/2021

If compression is now bad all the time, then get a leakdown gauge and see what you % leakage you get at 50psi. Higher pressure can force a marginal valve to temporarily seat. Vac gauge says valve fault. If the rockers move then it (almost) has to be valve(s) n... Login to read more.