Oil filter

[Skippydiesel]

Hi Grumpy Cat,

Strikes me that efficacy of non return valve will depend on;

• Quality of filter
• Column of oil above/below filter, providing additional sealing pressure (absent when you remove filter & allow to drain on side)

"Subaru Outback 2.5i filter is mounted open end down, with an “anti-drainback” valve. Filter will be empty 5 minutes after turning the engine off."
"2000 Toyota Avalon filter is mounted 45° down yet most all oil gets sucked out overnight in spite of the anti-drainback valve."

Interesting observations. How do you know? Have you remover filters at, say ,1 minute intervals, to check for retained oil quantity?

In the days before non return valves - on engine start up, you were supposed to wait (before revving/loading the engine) until oil pressure reached a desired level, indicating system full/circulating. In some engines this could take many seconds (especially those with many kilometers/hours) during which bearings/bushes may be running dry.
In modern engine the oil pressure no longer warrants a gauge, all that you get is a warning light, if pressure lost/not achieved. The only time you might see this light, is before engine start and after an oil change. The latter only showing for a brief moment or two, IF the mechanic has done a good job.
My Ford Ranger has a non return valve in the oil circulation system - not in the oil filter (as did my MB, 300D, W123), however all my other engines have the valve in the filter.

 

[GrumpyCat]

Hi Grumpy Cat,

Strikes me that efficacy of non return valve will depend on;

• Quality of filter
• Column of oil above/below filter, providing additional sealing pressure (absent when you remove filter & allow to drain on side)

"Subaru Outback 2.5i filter is mounted open end down, with an “anti-drainback” valve. Filter will be empty 5 minutes after turning the engine off."
"2000 Toyota Avalon filter is mounted 45° down yet most all oil gets sucked out overnight in spite of the anti-drainback valve."

Interesting observations. How do you know? Have you remover filters at, say ,1 minute intervals, to check for retained oil quantity?

As stated, Subaru OE filter (and Wix) is empty by the time I get around to removing from hot engine, 5 minutes. Avalon filter was bone dry overnight cold. The Avalon was particularly interesting because it made a huge mess when removed hot. 45° angle spilled oil on hot manifold and active motor mount. And most interesting as to be empty the oil had to be suctioned out as things cooled. Could not have emptied via gravity. On start it reached operating pressure quickly, but slower after an oil change, The mess is what prompted me to try cold. That it held full 5.0 quarts with filter cold, filter came off clean, 4.5 hot, filter made a mess, taught me to change that engine cold.

Have you done as I asked? Lay your used filter 1/3rd full on its side and observe oil leaking out or not? It will leak slowly through the anti-drainback valve. Which is most appropriately an anti-backwash valve.

In the days before non return valves - on engine start up, you were supposed to wait (before revving/loading the engine) until oil pressure reached a desired level, indicating system full/circulating. In some engines this could take many seconds (especially those with many kilometers/hours) during which bearings/bushes may be running dry.

Supposed to do that today too.

In modern engine the oil pressure no longer warrants a gauge, all that you get is a warning light, if pressure lost/not achieved.

Only get an idiot light because gauges cost extra and confuse today’s idiot drivers. Still get gauges on some vehicles. Admit some gauges are fake.

The only time you might see this light, is before engine start and after an oil change. The latter only showing for a brief moment or two, IF the mechanic has done a good job.
My Ford Ranger has a non return valve in the oil circulation system - not in the oil filter (as did my MB, 300D, W123), however all my other engines have the valve in the filter.

My F-150 has a cartridge filter which has to be opened to fully drain oil on change. Made mistake of draining oil before removing filter, filter must be out during drain. Else 8-16 oz remains resulting in overfill if full 6 quarts is added. Ford says allow 15 minutes after turning engine off to check oil level. Think it is trying to hold oil in pipes for minimal wear during Automatic Start Stop.

 

[Honest Abe]

next up, an 80-page thesis on oil viscosity and flow rate . . . . .

 

[ljb]

next up, an 80-page thesis on oil viscosity and flow rate . . . . .

Man, and all this started with my simple question lol.

 

[SamB]

Man, and all this started with my simple question lol.

You bad! But seriously, does the filter on any lawn/garden really do anything after the initial break-in period?
I realize that some machining shavings, etc may be circulating the first hour or two, but after that? One of my engines has a filter, but the others do not. So on the non-filtered ones, I just vac the oil out. As has been gone over a couple of times in this thread. the horizontal filter really holds no oil after shutdown. So, is vacuuming the oil out of that one a bad practice?

 

[Auto Doc's]

Hello SamB,

Nothing wrong with using a vacuum method to suction the majority of oil out through the dipstick tube. Even using the conventional drain on these engines will not empty all of the oil. (regardless of also tipping the engine as well).

All sumps have what I call "resting areas" where some oil and wear sediment will remain. Vertical engines have more of these areas.

As for changing the oil filter, I think that is important because the filter traps very fine wear particles constantly. Wear on any engine will produce microscopic particles and carbon deposits. The oil filter is vital. Oil does not wear out, it gets dirty.

Smaller engines do not typically have oil filters due to their small dimensions and displacement. These engines are also not built to last more than a few years even with proper oil maintenance.

 

[SamB]

Hello SamB,

Nothing wrong with using a vacuum method to suction the majority of oil out through the dipstick tube. Even using the conventional drain on these engines will not empty all of the oil. (regardless of also tipping the engine as well).

All sumps have what I call "resting areas" where some oil and wear sediment will remain. Vertical engines have more of these areas.

As for changing the oil filter, I think that is important because the filter traps very fine wear particles constantly. Wear on any engine will produce microscopic particles and carbon deposits. The oil filter is vital. Oil does not wear out, it gets dirty.

Smaller engines do not typically have oil filters due to their small dimensions and displacement. These engines are also not built to last more than a few years even with proper oil maintenance.

OK. That said, will it extend engine life to 'flush' these "resting areas" or are they best left alone? Let sleeping dogs lie, as it were?

 

[Skippydiesel]

"Have you done as I asked? Lay your used filter 1/3rd full on its side and observe oil leaking out or not? It will leak slowly through the anti-drainback valve."

Sorry Grumpy Cat - next servicing/oil change, probably several weeks away

"Which is most appropriately an anti-backwash valve."

Backwash - isn't that when you drink out of a bottle ?? Never heard this term used in relation to an engine.

 

[GrumpyCat]

"Have you done as I asked? Lay your used filter 1/3rd full on its side and observe oil leaking out or not? It will leak slowly through the anti-drainback valve."

Sorry Grumpy Cat - next servicing/oil change, probably several weeks away

So you never questioned the orthodoxy you read on the internet claiming the flap around the perimeter holes was to hold oil in the filter between starts? And never noticed oil running out of a used filter laying on it's side?

"Which is most appropriately an anti-backwash valve."

Backwash - isn't that when you drink out of a bottle ?? Never heard this term used in relation to an engine.

Are you here to only reafirm everything you have "learned" elsewhere?

When the engine stops running there is inertia in the motor oil moving through oil passages then suddenly not being pumped. It creates a suction as it stops, and then a shockwave travels backwards. This can knock stuff loose in the filter. The flap holds most in, only has to function for a fraction of a second.

 

[Auto Doc's]

OK. That said, will it extend engine life to 'flush' these "resting areas" or are they best left alone? Let sleeping dogs lie, as it were?

Hello SamB,

I would say "let sleeping dogs lie". Engine flush can easily do more harm than good because it is formulated with release agents. It may release clumps of aged sediment buildup that should not be circulated in the engine oil.