Where does the other end of this line connect? I'm pretty sure the oil filter bypass function is internal to the engine oil filter base shown at the top of the page below from the 1955.2-1960 GMC Master Parts Book.
By the way, if you are not a stickler for originality you can replace the complete filter assembly with a spin-on system from a later model Pontiac car. All real Pontiac V8 engines (last one built in 1981) use the same gasket between the block and the oil filter base, so later parts bolt right on. Most mount the spin-on filter cartridge straight down, but some tilt the bottom of the cartridge towards the driver's side a bit and certain hi-po models rotated the filter bottom towards the rear of the car some to clear headers. In any case, the spin-on filters are cheaper, easier to find and much less messy to change. I got the one I used on my 57 GMC 102 with a 347 V8 from a 1977 Pontiac full-size car at a local junk yard.
Last edited by Bill Hanlon; 03/17/20232:38 PM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
