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I might add that the above doesn't look like a bypass installation to me. Wonder if the bypass was a later change due to oil-starved hydraulic lifters?

All Packard straight 8s except the 1934-39 Super Eight and the 34-36 Eight have bypass filters. Ditto for the V8s.

So maybe the above cut-away is of a 39 super 8? The manual was printed September 1940 (second edition).

No, that's not a 39 Super 8, the entire construction of the old Eight/Super Eight engine is different, the most noteable external features being that the distributor is mounted to the cylinder head, oil pump below and fully enclosed in the sump, and the cylinder bores are cast iron and bolted to a cast aluminum crankcase. The other 8s, all based on the 1935 120 to one degree or another, have the oil pump external on the right side and driving the distributor which is on the left side and opposite.

In the engine as pictured, the oil emerges from the galley on the left side of the block where the oil pressure sensor is located, the flow is split, a portion (bypass) goes to the filter and the balance re-enters the block unfiltered to the return galley. Since less than 100% of the oil goes to the filter (probably about 7-15%), it is by definition a bypass filter.

Thanks Dave. Both the 356 engines I have are from the bathtub era with blocks cast in 1948, and 1949. I was unfamiliar with the '39's.

I guess I didnt look closely enough at the picture. You right the inlet is on the top, and the outlet is on the bottom. I guess next time I will study the picture more closely.

But on my other note, it is still not setup for By-Pass. Also when I went back and looked at the original 3 way "T" from my Non-By-Pass setup, it does has a restrictor in it. When I re-plumbed it By-Pass mode, the new 4 way "T" does not have this same restrictor in the filter outlet port.

Perhaps we should move this discussion over to the original thread some we dont hijack this thead anymore than I have already done!



Original Thread:

https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=896&viewmode=flat&order=ASC&type=&mode=0&start=0

The restriction is to maintain a high oil pressure for the hydraulic lifters by minimizing the flow to the filter and back to the crankcase. Many folks leave this out when they replumb the system (for God knows what reasons) and ultimately face the consequences if they keep the car. Also, some folks when installing a filter on a car that didn't have one remove the pigtail from the lower to the upper galley and instead put the filter return there, assuming that the filter flow will suffice. Bad idea for two reasons, (1) the restrictor, and (2) if the filter plugs, you loose oil to the lifters.

The 356 engine is perhaps Packards best since the Twelve. I've owned a couple and have serviced several others. Lovely engine.