Re: Retrovans 1972 Panel Van low light Bay
Posted: Thu Aug 20, 2020 3:02 pm
Test as I've mentioned below. Valves not opening can cause this. Just remove rocker covers and crank motor over to observe if rockers have full throw.
sean wrote: ↑Sun Aug 16, 2020 12:11 pm
2nd. Lifter / camshaft issue. A compression test may show compression 100%, but a failed lifter or lobe on a camshaft could cause this. If your compression is 100%, start motor with tappet covers off and inspect movement on the rockers. They should all have equal movement. If one rocker is not travelling the full distance, you may have a badly failed hydraulic lifter (but you should be able to hear this) or a lobe on the camshaft that has worn away (you cant hear this).
Another nice method I like to use other than a compression test is to measure the exhaust temperature of each manifold pipe. They should all more or less be equal in heat, a drastic temperature difference in one will point to the suspect.