I would put a gauge right on the fitting that the tubing originates from on the engine. It’s possible the fitting and or block is clogged at that point.

Here is one from Amazon.[LINK]

Last edited by Phak1; 08/30/2022 11:24 AM.

Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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