Re: Oil filter lines

Posted by HH56 On 2023/9/17 10:48:30

You can use the existing ports and leave the pigtail in place. That would duplicate the final plumbing arrangement Packard settled upon after intermittent issues with the filter and plumbing in early 356 engines with hydraulic lifters was found after a short time in production. That layout where return oil dumps directly into the crankcase was eventually on all engines made thru 56. Your port added in the fill tube is just an early implementation.

The engines with solid lifters like the 282 and later 288 do not require as much oil to the lifter gallery so lifter supply going thru the filter was OK. They left the return going to the upper port until somewhere in 23rd series production when hydraulic lifters became more the norm.

There may be a restriction somewhere in one of the fittings supplying your existing setup. It is unclear if that is needed with solid lifters as the demand is considerably lower so gallery will only be able to take a minimal amount of oil. No idea how much difference in flow there will be with a filter vs your present setup but if it turns out to be too much flow thru the filter and oil pressure gauge seems low compared to before, Packard added an orifice to one of the fittings to limit flow thru the filter to somewhere around 10-12% of what is available at the bottom port.

Prewar Packards had an orifice in the elbow fitting at the bottom filter inlet. That was later moved to a 4 way brass block fitting at the bottom port. Postwar the orifice was built into the center tube in the filter canisters. If you need to add something Packard advised adding solder to the fitting opening and then drilling a 5/64" hole thru the solder to act as the restriction.