Date: Tue, 5 Sep 95 10:28:12 EDT
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: John Anderson <ja@coe.wvu.edu>
Subject: Late F.I. Gas Lines
Now I know, we have all been over the importance of changing the
rubber lines, time and time again but I wanted to make some points
considering I have changed the lines on a '76, '77, and '78 as of
this weekend. The first thing I note is that VW seems to have
abandoned the famous cloth braided cover hose in late '76. My '76
had that hose, shielded between the sides of the fuel main ring and
the cold start valve by a grey sheath. This hose is the least I would
ever use for replacement, goes about $6 the meter from your local
VW supply house, hose clamps were the VW crimp style, likely most will
use standard stainless clamps as replacements. It takes about 2-3
meters to do a '74-'77 as the rubber hose goes all the way from the
tank to the fuel pump. Now imagine my suprise when the '77 does not
have the good old braided hoses. Instead it uses a hose that looks
more american in manufacture, having a smooth finely lined surface,
reinforcement sandwiched between 2 layers of rubber, and a spiral running
along the outside. Looks very much like some high pressure hydraulic
oil hose. Well the '77 also has the fuel pump relocated to the rear
frame rail above the rear wheel, not below the floor like a '76 (a
better safer location IMHO on the '77) and uses the standard VW crimp
clamps as well (these suckers can easily be chopped off BTW with a pair
of good high quality 8" diagonal cutters). Well the '77 also eliminates
the sheath over the lines on the fuel main ring which I knew cloth
braided hose Buses had so I was leery to substitute the older hose. A
quick look through the Automotion (Porsche people, good catalog if you
can get a copy since 914/Bus overlap at times) catalog reveals the
correct stuff, this is German "smooth pressure hose" they call it in
their fuel line section, same ID as the other, OD is a bit smaller,
goes about $10 the meter (ouch), I ordered some and it is exactly like
OEM. Well the confusion of course does not end with the '77, and in
fact the '78 is what I really want to talk about as I think some major
steps were taken backward in fuel system safety. For '78 VW went into
fuel system paranoia, the heater flapper boxes have hoods that channel
the heat away to a couple of exhaust tubes mounted on the engine support
points (a good idea I always worried about all that heat getting dumped
right under the fuel hoses on both sides), and there is a blanket of
aluminum faced insulation under the entire tank area held up by little
metal tabs (this I don't care for as the insulation holds water against
the body with predicatable results), but what is really troublesome is
that VW got some great idea about going to copper clad steel fuel lines
on the exterior of the car with short smooth rubber hose jumpers between
the tank and the steel line, the steel line and the filter, etc. etc.
The first thing I don't like is that this mean twice the connections on
the rubber lines, meaning you need twice the clamps and have twice the
opportunity for your current lines to be leaking. Clamps on the low
pressure side are crimp, on the high pressure side are VW type screw
hose clamp. Now guess what IF YOU REPLACED YOUR RUBBER LINES WITHOUT
LOOKING AT THE STEEL LINES, GO BACK NOW!! The steel lines on the
outside of the car may look good from below but on my '78 (a not run in
winter generally rust free bus) the tops of the lines were fairly
corroded right through the copper cladding, not bad but would have been
in a little while, particularly the small line from fuel pressure
regulator to the return port in the tank. Moreover a TRAGIC design flaw
came about, the steel line from the left side injector bank was extended
through the firewall, where previously a flexible hose had passed. The
typical VW rubber grommet solution was maintained, personally I like the
rubber hose going through better as it being less rigid could vibrate
freely, the steel line simply wears down the grommet and eventually I
imagine itself. My solution was to rotate the grommet to a more unworn
position and sleeve the steel line with a 1" piece of cloth braided hose
slit down the side and slid to the appropriate position. Now for the
last little bitch, and this goes for air cooled and maybe H20 Vanagons
as well. the steel lines from injector bank to cold start valve looked
great, no corrosion, but since I was changing the rubber ends I took em
out and lo and behold, THE CABLE TIE SECURING THEM TO THE INTAKE
MANIFOLD RUNNERS HAD SEVERELY ABRADED THE SURFACE OF THE LINES!! Here
again as mine didn't look that bad and replacements were not readily
available I sleeved them with a piece of old fuel line and cable tied
around that. On the rusted exterior lines I half thought about replacing
with rubber like the '77 but instead, cleaned them well, degreased them
and sprayed with rust resistant zinc paint, maybe not as good a solution
as I should do, I note that the long line between tank and fuel filter
was rusting UNDER A LAYER OF UNDERCOATING, so don't assume you are OK,
be sure.
Sorry this has gone on so long
Safe driving everyone.
John (ja@coe.wvu.edu)
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