Date: Wed, 6 Oct 2010 15:30:36 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Fuel Filters vs Fuel Strainers
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Then one wonders why VW thought it adequate on 86 and later vans to have only the large downstream filter.
I don't regard the pumps as delicate or very vulnerable to anything coming from the tank.
They seem to be able to endure almost anything, more or less.
----- Original Message -----
From: John Rodgers
To: Scott Daniel - Turbovans
Cc: vanagon@GERRY.VANAGON.COM
Sent: Wednesday, October 06, 2010 2:48 PM
Subject: Re: Fuel Filters vs Fuel Strainers
I have that little square strainer on all three of my vans - two 88 GLs and one Carat. Dunno who put them there, but there they are, and I'm glad of it.
But I think you have missed the point(s) (1) The strainer is to PROTECT THE FUEL PUMP from the large particles of crude that could damage the internal components of the pump. (2) The can type filter is there to PROTECT the fuel injectors by taking out the very fine stuff that could get caught in the nozzles of the injectors. Having a larger can filter downstream of the pump gains no advantage in protecting the pump. Only something upstream would do that - whether a screen in the tank or a strainer before the pump. Unless it is known for certain there is a screen n the tank, I certainly would opt for the small strainer in front of the pump. Good insurance.
John
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com
On 10/6/2010 4:06 PM, Scott Daniel - Turbovans wrote:
re
"Both are lifetime filters and do not require replacement under normal
circumstances."
That's totally silly, I hope you don't believe that for a second.
I would say this book does not match vanagons exactly.
it's a 'digifant' manual.
Digifant Vanagons ( 2.1 wbxr engine ) use one 'large silver can fuel
filter' downstream of the fuel pump.
that's all they have ..
unless you count some sort of strainer or screen that is likely in the fuel
tank.
the 'small square filter' as we know is used on DigiJET Vanagons with 1.9
engine ..
and it's before the fuel pump, and it's the only fuel filter on those vans
( it's always better to eliminate that small filter and put the larger metal
can filter on those vans, downstream of the fuel pump )..
And it is a filter for sure, not a strainer.
I never take Manuals like this as Pure Gospel ..
They are very much in the ball park about most things ..
but they are more 'system' related, rather than specific vehicle related,.
I regard them as an overview to find out how the system they cover works. .
and not so much for vehicle specific details.
Scott
www.turbovans.com
----- Original Message -----
From: "John Rodgers" <inua@CHARTER.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, October 06, 2010 1:26 PM
Subject: Fuel Filters vs Fuel Strainers
In working with my two vans that were stored for 10 years, I have had
to deal with many issues. One was getting the fuel delivery system
working again. This included opening it up, and flushing all the old
fuel and junk from it. The injectors were frozen and would not work, so
had to send them out for servicing. They work fine now. And the fuel
pump on my Carat was seized so that had to be dealt with. By removing
the pump, and spraying carburetor cleaner into it and allowing it to sit
over night, then repeating the process, the pump freed up and now works
just fine.Then there was the issue of the fuel filters.
In as much as I'm having idling problems, I got out the Digifant Fuel
Injection System manual to study. I found interesting remarks concerning
the fuel filters. In as much as there has been a good bit of talk on
this list about the large filter after the pump, and the small filter in
front of the pump - here is what the book has to say about them.
************************
*Fuel Filters*
Two types of filters are used on the Digifant system.
One is a square _*plastic fuel strainer*_ which is mounted before the
fuel pump *_to __protect the pump_* from foreign particles.
The *_main fuel filter_* is a metal cylinder which mounts behind the
fuel pump. *_It has a finer filtering mesh to protect the fuel injection
components._*
Both are lifetime filters and do not require replacement under normal
circumstances.
*********************
Of interest to me is the different function of the two filters - the
first to protect the pump. the second to protect the FI components, ie,
the injectors.
I note that one is a fuel STRAINER, while the other is a fuel FILTER.
Quite a different between a strainer and a filter.
I have read that the square strainer can be left out, but after reading
this - I would not. Each filter/strainer serves a different and distinct
purpose and therefore both need to be in the fuel system..
Just my $0.02.
John
--
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com