Date: Mon, 4 Sep 2006 22:35:34 -0400
Reply-To: Dennis Haynes <dhaynes@OPTONLINE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: Re-useable oil filter
In-Reply-To: <20060830043430.54157.qmail@web56409.mail.re3.yahoo.com>
Content-type: text/plain; charset=us-ascii
The proper oil filter for the Vanagon WB and most vehicles has an anti-drain
back valve. It is basically a diaphragm under the oil inlet which is that
series of holes on top of the filter. The air cooled Vanagon filter does not
get one. Most vehicle engines also get the bypass valve. This is used if the
filter gets clogged and/or to allow that inrush after strt up if the oil is
too viscous to go through the media, (filtering material). The VW in line
engines and the air cooled have the bypass valve in the oil filter adapter.
The Water Boxer does not and that is why it uses a different filter number
if using a Mann or Mahle filter. Most of the remaining aftermarket says that
an extra bypass valve is not an issue so the infamous Fram PH2870A is used
for both. If you cross reference other brands, you will also find the PH3600
is usable.
As for the choice of filter affecting lifter clatter or oil pressure
problems, this is the Hokum. While I agree that the Mann and Mahle filter is
a higher quality, maybe better designed part, if the difference of a 1-2 psi
pressure drop makes a difference, the engine is in trouble anyway. As for
the drain back valve holding the oil in the lifters, one does not know how
they work. Shutting down a warm engine, there is no residua l oil pressure
anywhere except inside the lifters, and any under an open valve will bleed
down eventually. As for the design and wall thickness of the can, the older
water cooled engines that operated at 90 psi warm and a lot colder, needed
good filters. Our engines that barley muster up 75 cold and less than 50
warm do not know the difference. I remember blowing up many a Purolator on a
76 Scirrocco.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Tabe Johnson
Sent: Wednesday, August 30, 2006 12:35 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Re-useable oil filter
Mike/List,
This is a load of hokum that has been going 'round the list
for a while. The only valve in any oil filter is a bypass valve
which would activate itself if the filter media got too clogged to
pass enough oil, for instance.
Let's see: How would a valve that kept the lifters from bleeding
down work? It would apply oil pressure. Where does oil pressure
come from? The oil pump. When the engine's off, the pump's off.
So when the engine's off, there's no oil pressure, regardless of
how many valves you have in your filter.
tabe johnson/87 westy
PS - speaking of hokum, (and I'm not trying to be aggressive - just
asking the question) how is it that replacing just one of the two
pneumatic rear hatch struts can cause it to fail prematurely? One
strut doesn't know what the other is doing. It's just applying
pressure to a piston, right?
*** cut here ***
Date: Tue, 29 Aug 2006 21:58:33 -0400
From: Mike Collum <collum@VERIZON.NET>
Subject: Re: Re-useable oil filter
But what about the valve in the filter that keeps the lifters from
leaking down?
Mike