Removing and installing fuel tank shut-off valve, solenoid valve with securing clip — VW

Removing and installing fuel tank shut-off valve, solenoid valve with securing clip
WARNING
Tank shut-off valve must not be removed until respective tank has been drained completely.
Special tools and workshop equipment required
Engine and gearbox jack
V.A.G 1383 A
Tensioning straps
T10038
or
tensioning straps
T10523
(not illustrated)
Bracket for gas tank
T 10351
Special wrench
T10350
Torque wrench
V.A.G 1332
Removing
Fuel tank must be at room temperature (at least 15 °C).
Observe safety precautions
Chapter
.
Observe rules for cleanliness
Chapter
.
Observe safety precautions when working on natural gas system
Chapter
.
Read system pressure using
Vehicle diagnostic tester
.
Select
Guided functions
.
Read
Measured values
for "Gas tank – interior pressure" in "Engine" option.
Take care not to damage painted surfaces when working on fuel tanks.
If necessary, protect painted surface with suitable workshop equipment.
Remove fuel tank
Chapter
.
Secure fuel tank
1
on
engine and gearbox jack
V.A.G 1383 A
and
bracket
T10351
using
tensioning straps
T10523
, as shown in illustration.
Ensure that the ratchets of the tensioning straps are offset, as shown in illustration.
Secure fuel tank
1
with both
tensioning straps
T10038
.
Draining fuel tank
Chapter
Thoroughly clean area around
fuel tank shut-off valve
.
Perform back pressure check
Chapter
.
Mark the position of the valve relative to the fuel tank.
Carefully loosen fuel tank shut-off valve using
special wrench
T10350
1
.
Ensure proper seating of guide of
special wrench
T10350
.
Using
special wrench
T10350
, loosen and unscrew
fuel tank shut-off valve
as follows:
Caution
Always follow the procedure below when unscrewing the
fuel tank shut-off valve
.
Procedure for unscrewing
fuel tank shut-off valve
Carefully loosen
fuel tank shut-off valve
using
special wrench
T10350
.
Note
The O-ring will slip out of the groove while doing so and will allow for any residual gas to escape.
Depending on the residual pressure, a loud noise may be audible when the O-ring is released from the sealing surface.
Slowly unscrew
fuel tank shut-off valve
by up to a half turn so that residual gas can escape.
DANGER!
As soon as you can hear residual gas escaping, do not unscrew the
fuel tank shut-off valve
any further.
Wait until no more gas can be heard to escape before continuing work:
Checking play on
fuel tank shut-off valve
:
Carefully move
fuel tank shut-off valve
in
directions of arrows
.
The
fuel tank shut-off valve
must not be unscrewed any further while doing so.
There must be a slight play.
Let more residual gas escape.
DANGER!
Wait until no more gas escapes before carefully unscrewing the
fuel tank shut-off valve
further.
Unscrew
fuel tank shut-off valve
further in 90° steps.
Unscrew
fuel tank shut-off valve
further by a maximum of 2 turns.
DANGER!
If no gas has escaped and no play can be observed, after the fuel tank shut-off valve has been unscrewed by 2 turns, do not unscrew the fuel tank shut-off valve any further.
If no residual gas has escaped:
Tighten fuel tank shut-off valve to 130 Nm.
Do not perform any work on the fuel tank or the
fuel tank shut-off valve
.
If the residual gas has escaped and play can be observed:
Unscrew
fuel tank shut-off valve
.
Observe rules for cleanliness
Chapter
.
Observe safety precautions when working on natural gas system
Chapter
.
Remove any wax residue.
Installing
Install in reverse order. Observe the following:
Note
Lightly coat seal with engine oil or Vaseline.
There must not be any wax on the thread.
No wax must be allowed to get into the fuel tank.
No wax must be allowed to get into the lines.
Fit new seal
2
on fuel tank shut-off valve
1
.
Screw fuel tank shut-off valve
1
into fuel tank
3
.
Tighten
fuel tank shut-off valve
to 130 Nm using
special wrench
T10350
.
Install fuel tank
Chapter
.
Check natural gas supply system for leaks
Rep. gr.
24
Checking natural gas supply system for leaks
.
Perform gas system test
Maintenance
Booklet
35.1
Description of work; Performing visual inspection of natural gas tanks for corrosion and leakage test
.
Coat connection between fuel tank
1
and
fuel tank shut-off valve
2
with wax.
For allocation of wax refer to
Electronic Parts Catalogue
.
Spray wax into the cap of the spray bottle.
Use a suitable, commercially available brush to apply the wax.
Apply a thin coat of wax all around
arrows
.
Note
There must not be any wax on the thread.
No wax must be allowed to get into the fuel tank.
No wax must be allowed to get into the lines.
Specified torques
Component
Specified torque
Tank shut-off valve on fuel tank
130 Nm
Pipe inserts on tank shut-off valve
20 Nm