Dual oil fillers

[kare]

You may be right or wrong about oil flows, I don't know. The only reference I once read about this handled earth moving equipment and there it was stated that oil volume through by-pass is much higher than on main filter. This was also used to reason why the use of by-pass filter is able to keep the oil significantly cleaner. With low oil flow it would have much lesser significance. Most particles come from blow-by so they end up in the sump. From then on likeliness to end into a certain filter comes from the division of filters and if the by-pass flow is low, the by-pass filter does not have a real purpose. This is why the system is normally designed so that the by-pass keeps oil clean and main filter screen the main stream so that it is 100% sure no eventual particle ends up damaging bearings or restricting oil flow in passages. I have no idea if this is the case with a Ferrari; it is a slightly different beast comparing to a Caterpillar.

It would be tempting to think that the very small hole in pressure plate/exit passage of PB50 would help to determine that the oil flow through by-pass must be very low, but to be honest I have no idea which gives greater back pressure: a bottle neck of a 1 mm hole restricting PB50 or the oil passages and bearings restricting the flow through main filter. Knowing the volume through oil pump I would say there is no way bearings can consume that much oil, so most of the flow should go back into sump through by-pass... but as said earlier I am only guessing here.

Best wishes, Kare

[DWR46]

The excess oil flow from the pressure pump returns to the sump via the bypass/pressure regulating valve on the chaincase. We have too many "bypass" items here, the actual engine bypass in the chaincase and the PB50 filter, which is a "bypass style" oil filter. Each do different jobs, and have no connection to each other.

[kare]

I asked the local Badlwin representant while ordering some fuel and oil filters for my car. He said that flow through by-pass is lower and filtration finer. Best wishes, Kare

[Yale]

From the web --
By pass oil filters provide the best possible filtration protection against wear and oil degradation. Working in conjunction with the engine’s full-flow oil filter, the by pass filter operates by filtering oil on a “partial-flow” basis. It draws approximately 10 percent of the oil pump’s capacity at any one time and traps the extremely small, wear-causing contaminants that full-flow filters can’t remove. The by pass filter typically filters all the oil in the system several times an hour, so the engine continuously receives analytically clean oil.

[carello]

Which one is bypass and which is normal?
Are there published technical specs on the Fram numbers referenced?
PH3, PB50 ?
Was OEM equipment the orange Fram filter cartidges?
thanks
Craig

[DWR46]

In the drawing, #3 is full-flow, and #6 is bypass. I belueve the old PH3 was discontinued many years ago.

[330GT]

I belueve the old PH3 was discontinued many years ago.

True, replaced with the PH2815.