Here's the truth about the difference between the AC PF 58 and PF 59

[Mike_dup1]

Just to clarify the photo above, the rubber for the PF58 is not a valve, just a spacer. It a hard rubber.

The other 2 filters, 59 and the Fram, the rubber is a valve, teh 59 is very soft and the Fram is much harder. It blocks the holes in the filter base preventing flow when engine is not running on the 59 and Fram.

 

[dickwells]

What Alex D. said. I hope we can get beyond the idea that if the filter is upright it does not need a check valve (or whatever you wish to call it). To prove this just observe how much oil drains out of your engine with upright filter when you first loosen the filter. This is the oil that will drain down through the filter overnight or be retained by a valve so that your cam and lifters run dry for a much shorter time when you start up. Regards, RW

 

[G-MAN]

quote:

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Originally posted by dickwells:
What Alex D. said. I hope we can get beyond the idea that if the filter is upright it does not need a check valve (or whatever you wish to call it). To prove this just observe how much oil drains out of your engine with upright filter when you first loosen the filter. This is the oil that will drain down through the filter overnight or be retained by a valve so that your cam and lifters run dry for a much shorter time when you start up. Regards, RW

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Huh? An anti-drainback valve is just that: it prevents oil from draining back OUT of the filter and into the oil pan. If the filter is mounted completely vertical (and upright, not upside down), then gravity will prevent the oil from draining back. Drain back is a physical impossibility in an upright mounted filter, hence an antidrainback valve is not necessary.

 

[dickwells]

Hmmm, it seems I failed in my previous effort so I will try again. The oil that is up in the passages has to pass through the filter before draining back down into the pump and pan. The valve interrupts the path of the oil so it cannot flow through the filter in a reverse direction, thus it is retained up in the cam and bearing passages at least for a lot longer than if there is no valve. A review of a lubrication passage drawing of an engine is appropriate at this point if you can find one. When the engine is off there is a reverse pressure applied through the filter by gravity acting on the oil in the passages and it attempts to find its own level (the oil pan)unless stopped by the valve in the oil filter. (end lecture ll)

 

[RobZ71LM7]

quote:

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Originally posted by XHVI:

quote:

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Originally posted by dickwells:
What Alex D. said. I hope we can get beyond the idea that if the filter is upright it does not need a check valve (or whatever you wish to call it). To prove this just observe how much oil drains out of your engine with upright filter when you first loosen the filter. This is the oil that will drain down through the filter overnight or be retained by a valve so that your cam and lifters run dry for a much shorter time when you start up. Regards, RW

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Huh? An anti-drainback valve is just that: it prevents oil from draining back OUT of the filter and into the oil pan. If the filter is mounted completely vertical (and upright, not upside down), then gravity will prevent the oil from draining back. Drain back is a physical impossibility in an upright mounted filter, hence an antidrainback valve is not necessary.

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B.S. Then why when I remove the filter from my truck that's sat for several days do I get a pint of oil running down as soon as the seal is broken? My truck ha valvetrain noise when I used a pf58 in it but with a pf59 it makes no noise at all.

 

[Terry]

Golly that Fram is a poorly built filter

 

[G-MAN]

quote:

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Originally posted by RobZ71LM7:

B.S. Then why when I remove the filter from my truck that's sat for several days do I get a pint of oil running down as soon as the seal is broken? My truck ha valvetrain noise when I used a pf58 in it but with a pf59 it makes no noise at all.

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BS? Explain to me how oil can drain UP and OUT of a filter that's mounted upright? Granted if the filter is not exactly vertical, and it doesn't have an antidrainback valve, some oil will drain back. But if the filter is completely vertical (as was the case with the old small block Chevys), drainback is impossible.

 

[Terry]

XHVI, The anti drainback valve acts like a really cheap accumulator to keep a level of lubricant in "place" on start. Like head pressure on a hydraulic system.

A picture or graphic will really help on this, Bob used to have some great graphics that were even dynamic to show oil flow in the average engine, wet sump. Can someone more computer literate help find that graphic ?

No need to get testy fellas we all can learn alot from one another, I remember a....no most of my math teachers... no most of my teachers getting irritated when I didn't get it the first,2nd,3rd time around.

 

[RobZ71LM7]

quote:

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Originally posted by XHVI:

quote:

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Originally posted by RobZ71LM7:

B.S. Then why when I remove the filter from my truck that's sat for several days do I get a pint of oil running down as soon as the seal is broken? My truck ha valvetrain noise when I used a pf58 in it but with a pf59 it makes no noise at all.

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BS? Explain to me how oil can drain UP and OUT of a filter that's mounted upright? Granted if the filter is not exactly vertical, and it doesn't have an antidrainback valve, some oil will drain back. But if the filter is completely vertical (as was the case with the old small block Chevys), drainback is impossible.

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Why should I have to explain it? The real-world results make it more than evident that a good anti-drainback valve is essential even in vertically mounted filters. The 5.3L does have a vertically (not angled at all) mounted oil filter...about 1/2 a quart always drains out when it is loosened-not what is inside the filter. If you're correct then explain to me why 5.3L's tick with pf58's on startup and not pf59's.

 

[RobZ71LM7]

After re-thinking my reply it was worded a little harshly sorry if it came across that way.

 

[G-MAN]

quote:

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Originally posted by Terry:
XHVI, The anti drainback valve acts like a really cheap accumulator to keep a level of lubricant in "place" on start. Like head pressure on a hydraulic system.

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Fair enough. And that's a plausible explanation for why the PF59 is effective in preventing lifter noise at start up. However, that's not the same thing as saying that an upright mounted filter suffers from "drainback."

 

[Patman]

quote:

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Originally posted by Terry:
Golly that Fram is a poorly built filter

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Definitely! Now we have to convince our dear friend Bob to stop using them!

 

[Terry]

XHVI,It doesn't matter where the filter is mounted, when a dynamic pressurized wet sump hydraulic system has the oil pump shut off, with no check valves or accumulators to hold the oil in place, the oil searches for the low ground( cavities) as far as gravity can move it.

Sometimes the noise you hear on start can be the oil pump,or lower end bearings/components not just valve train, when the oil drains out of is normal dynamic locations.

XHVI, I don't know if you have picked up on this but this board was designed by Bob and helped by a few others of us to be a healthy non threatening discussion site, Brands and opinions be ****ed.

I appreciate your exchanges and have really enjoyed the Synthetic discussions. No need to be defensive or hurt.
Everyone here really learns alot and has a good time. NO ONE HAS A LOCK ON every aspect of what is shared here unless you are PATMAN !

Bob and I have done alot of this

and still sat down here in Greenville for some good Mexican food !

[ December 05, 2002, 11:04 AM: Message edited by: Terry ]

 

[G-MAN]

quote:

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Originally posted by Terry:
XHVI,It doesn't matter where the filter is mounted, when a dynamic pressurized wet sump hydraulic system has the oil pump shut off, with no check valves or accumulators to hold the oil in place, the oil searches for the low ground( cavities) as far as gravity can move it.

....

XHVI, I don't know if you have picked up on this but this board was designed by Bob and helped by a few others of us to be a healthy non threatening discussion site, Brands and opinions be ****ed.

I appreciate your exchanges and have really enjoyed the Synthetic discussions. No need to be defensive or hurt.

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The only time I might get a little defensive is when someone says what I posted is BS. But I don't get hurt over it.

As far as the topic, you'll never convince me that the oil in an upright mounted filter that is completely vertical will drain back. Ain't gonna happen. Gravity will keep whatever oil is in the filter at shutdown in the filter.

The only way I can see that the filter would evacuate is if some sort of siphoning effect took place, pulling the oil out of the filter and into the pan. I don't think this happens, however, because the whole reason some filters are made with no antidrainback valves is for upright installations.

 

[dickwells]

Looks like we are beating a dead horse here, but the valve is not present for the oil in the filter, it is present for the oil up in the passages which will drain out through the filter. This reminds me of when I had an engineer who could not understand that two cars colliding at 60mph was not the same as a car hitting a brick wall at 120mph. Have I been had by a Troll?

 

[G-MAN]

quote:

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Originally posted by dickwells:
Looks like we are beating a dead horse here, but the valve is not present for the oil in the filter, it is present for the oil up in the passages which will drain out through the filter. This reminds me of when I had an engineer who could not understand that two cars colliding at 60mph was not the same as a car hitting a brick wall at 120mph. Have I been had by a Troll?

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I think you are absolutely wrong about this. The anti-drainback valve is there to prevent the oil in the filter from draining back into the engine when the engine is shut-off. By default, this may keep oil upstream of the filter, but the purpose of the valve is to avoid "dry starts" from an empty oil filter.

 

[dickwells]

I give.

 

[Terry]

UNCLE !!!

 

[Patman]

I don't see the problem. Having an oil filter with an antidrainback valve won't cause any harm, but running without one could possibly do more harm, so why take the chance? All of my cars from now on will use filters with the ADBV in them.

 

[G-MAN]

quote:

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Originally posted by Patman:
I don't see the problem. Having an oil filter with an antidrainback valve won't cause any harm, but running without one could possibly do more harm, so why take the chance?

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I agree 100%