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Was: question about oil filter change,now: different question about oil filter change



It's the old "if it's properly engineered" thing.
In the course of my job I specify a lot of different types of springs. Coil 
spring here, belleville washer there, leaf spring somewhere else.
One is not inherently better than the other. Just a different combination of 
travel, stiffness and shape.

But, let's get to the heart of the matter.
Is it a bypass valve or an anti-drain back valve?

If it's a bypass valve, i.e.it bypasses the filter media due to excessively 
high pressure across the media, then, guite frankly, who gives a shit??
If you change your filter so infrequently that it clogs, then you don't give 
a shit about your engine or what filter you use.

If it's an anti-drain back valve then I have to say the same thing. Who 
gives a shit?
The filter is virtually vertical in our applications and the oil isn't going 
to run out of it anyway when the engine isn't running.
I've seen applications where the filter is horizontal or upside down (older 
Ferrari's believe it of not! Right on top of the engine, two of them, just 
so you have to spill a quart of oil over the engine to change them!) where 
the oil will drain out without a valve. Then it would matter how well the 
valve performs.

As far as the filter media itself, how thick is thick enough? Is thicker 
always better? How much pressure drop do you want across the filter? Is the 
media exactly the same material? Is one material better than another?
I'm sure there are lots of other engineering concerns in designing a filter. 
I don't know the answer to those questions. And I suspect nobody else on the 
list does either.
The bottom line is how effectively does it filter, and my experience says it 
works just fine. No failures and the condition of the engine after 140,000 
miles showed virtually no wear. Not a scientific test, but I'm happy ;^)

Dan

----- Original Message ----- 
From: "David Utley" <fahrvegnugen@cox.net>
Subject: RE: Was: question about oil filter change,now: different question 
about oil filter change


> Compare the filtering medium between the two; the fram is nearly half as
> thick, the bypass valve is a sprung piece of flat steel vs. a coil spring.
> IIRC, the flat spring could fault and not work at all because of how it 
> was
> made and positioned, while the coil spring will work regardless of what
> happens (barring nuclear war...  :))
>
> Dan, have you cracked one open before?
>
> Use what you like, it is ultimately up to the installer.
>
> David
> -----Original Message-----
> From: Dan Bubb [mailto:jdbubb@verizon.net]
> Sent: Saturday, July 09, 2005 10:19 PM
> To: David Utley; Larry Fry; GGehrke
> Cc: Scirocco list
> Subject: Re: Was: question about oil filter change,now: different question
> about oil filter change
>
> As I said in a previous post, I've used Fram for a long time with no ill
> effects.
> So I suspect the statement below is opinion and should be taken as such
> until some FACTS are presented.
>
>
> ----- Original Message -----
> From: "David Utley" <fahrvegnugen@cox.net>
> Subject: RE: Was: question about oil filter change,now: different question
> about oil filter change
>
>
>> Simply put, FRAMS suck donkey dick.
>
>
>