Ford 9N Oil Filter...Is it supposed to have one?

Tim

Most modern engines have "full flow" oil filters that filter 100% of the oil from the oil pump that goes to the engine bearings. Because of the large volume of oil that must be filtered,the "full flow" filter is not as "tight" and will not filter out the smallest particles in the oil. Many large diesel engines have the best of both filter systems,as they have both full flow and bypass filters installed on the same engine.

A bypass filter only sees the oil that is released from the pressure lines by the oil pressure regulator valve. The main oil flow goes directly from the pump to the bearings. The excess goes to the bypass filter. Its not as good as a full flow filter that is the modern standard, but it was much easier to retrofit to an engine and was better than no filter at all.

Gerald J.

Where did you get an idea like that???

The "N" Ford's oil pressure regulator valve, located at the front of the engine

dumps any excess oil into the timing gear area, where it returns to the crankcase.

The bypass filter is fed oil from the main oil gallery at the REAR of the engine, and a simple (tiny) oriface limits flow OUT of the filter canister, so that only a small amount of oil flows through the filter assembly, so as no to drop the engine's oil pressure too much.

AFAIK, ALL the 9N's, 2N's and 8N's would have had oil filters, from the factory.

Originally, the filtered oil was simply dumped into the crankcase. At some point, a change was made where the return oil from the filter was piped to the other side (RH) of the engine, where it was returned to the crankcase through the governor, lubing it on the way.