Just like truckernix points out, if there is no restriction at the filter or any of the lines between the "T" that leads to your gauge and the opening to the crankcase you will show low pressure.

I suppose there could be a restriction in one of the fittings like the one in the pipe leading to the rocker arm & shaft area.

truckernix where is the one in your filter and what does it look like?


1941 Chevy Master 3/4-Ton
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