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twas_brillig
Jedi Knight
Offline
My brother Ric (a retired, legitimate, auto mechanic) pulled together the following information for me on oil filters from our friend Google (and if anyone is using a spin-on with these various features - please advise):
1): The anti-drain back valve prevents oil from draining out of the filter when the engine is turned off.
During an oil change, it’s recommended you put fresh oil in the new filter before installing it. This is so oil is available to the engine as soon as it’s started.
The anti-drain back valve serves a purpose that’s similar to this oil change strategy. Every time your engine is shut off, the valve keeps oil from draining out of the filter. This allows the engine to receive oil immediately upon start up.
A faulty anti-drain back valve lets oil drain back into the engine. This keeps oil from getting to the engine when it’s first started. The result is engine wear and eventual failure from lack of lubrication. Low-quality oil filters often have a poorly designed anti-drain back valve that doesn’t work properly.
2): three types of valves that can be found in spin on filters:
Anti-drain back valve:
This valve is most often in the form of a rubber membrane adhering to the inner side of the spin-on filter cover. This membrane obscures the holes through which dirty oil gets into the filter. The purpose of the anti-drain back valve is to prevent the oil from escaping from the filter when the engine is switched off. The anti-drain back valve is required in filters screwed from the side or top of the engine body (if the filter’s cover is facing upward, gravity assumes the function of the valve).
Bypass valve
The bypass valve is used when the filter is clogged due to a long period of time between replacements or when the vehicle is running at a low temperature (when the oil is cold and dense). The bypass valve is opened as a result of the pressure increase in order to increase the throughput of oil flow in the engine as there may be a risk of insufficient lubrication of the parts working together. The use of a bypass valve results from the fact that dirty oil is always better for the engine than its total absence. A lack of oil lubrication can damage the engine.
Anti-syphon valve:
This valve prevents the oil from running out of the filter when the engine is switched off. It has a function similar to that of the anti-drain back valve - with the difference that the valve is placed on the "clean side" of the filter. As a result, the filter is constantly filled with oil, regardless of whether the engine is running or not. After starting the engine, the anti-syphon valve significantly reduces dry friction between the parts working together, as it contributes to the rapid flow of oil to the engine.
1): The anti-drain back valve prevents oil from draining out of the filter when the engine is turned off.
During an oil change, it’s recommended you put fresh oil in the new filter before installing it. This is so oil is available to the engine as soon as it’s started.
The anti-drain back valve serves a purpose that’s similar to this oil change strategy. Every time your engine is shut off, the valve keeps oil from draining out of the filter. This allows the engine to receive oil immediately upon start up.
A faulty anti-drain back valve lets oil drain back into the engine. This keeps oil from getting to the engine when it’s first started. The result is engine wear and eventual failure from lack of lubrication. Low-quality oil filters often have a poorly designed anti-drain back valve that doesn’t work properly.
2): three types of valves that can be found in spin on filters:
Anti-drain back valve:
This valve is most often in the form of a rubber membrane adhering to the inner side of the spin-on filter cover. This membrane obscures the holes through which dirty oil gets into the filter. The purpose of the anti-drain back valve is to prevent the oil from escaping from the filter when the engine is switched off. The anti-drain back valve is required in filters screwed from the side or top of the engine body (if the filter’s cover is facing upward, gravity assumes the function of the valve).
Bypass valve
The bypass valve is used when the filter is clogged due to a long period of time between replacements or when the vehicle is running at a low temperature (when the oil is cold and dense). The bypass valve is opened as a result of the pressure increase in order to increase the throughput of oil flow in the engine as there may be a risk of insufficient lubrication of the parts working together. The use of a bypass valve results from the fact that dirty oil is always better for the engine than its total absence. A lack of oil lubrication can damage the engine.
Anti-syphon valve:
This valve prevents the oil from running out of the filter when the engine is switched off. It has a function similar to that of the anti-drain back valve - with the difference that the valve is placed on the "clean side" of the filter. As a result, the filter is constantly filled with oil, regardless of whether the engine is running or not. After starting the engine, the anti-syphon valve significantly reduces dry friction between the parts working together, as it contributes to the rapid flow of oil to the engine.
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