Removing and installing fuel tank, four-wheel drive — VW

Removing and installing fuel tank, four-wheel drive
Caution
The fuel pump must not be allowed to run when the fuel tank is empty, as this may cause deflagrations.
The fuel tank must contain at least 5 litres of fuel.
Note
Before carrying out further work, disconnect the battery. For this reason, first check whether a coded radio is fitted. Obtain anti-theft coding beforehand if necessary.
When lowering fuel tank, guide it carefully to prevent damage.
Special tools and workshop equipment required
Torque wrench
V.A.G 1332
Fuel tank sender unit tool
T10202
Removing
Check whether a coded radio is fitted. If so, obtain anti-theft coding.
Disconnect earth cable at
battery
with ignition switched off
Rep. gr.
27
Disconnecting and connecting battery
.
Drain fuel tank with
fuel extractor
VAS 5190
Chapter
.
Unclip rubber cup from filler neck.
Unscrew bolts
3
on filler neck
1
.
Remove rear left wheel.
Remove rear left wheel housing liner
General body repairs, exterior
Rep. gr.
66
Wheel housing liner; Removing and installing rear wheel housing liner
.
On Caddy Maxi, unscrew bolt
arrow
for filler neck on side member.
WARNING
The fuel and the fuel lines in the fuel system can become very hot (danger of scalding)!
The fuel system is also under pressure! Before opening the system, place cloths around the connections. Then carefully loosen connection to release the pressure!
Wear eye and hand protection when performing any type of repair work on the fuel system!
Separate fuel lines
1
and
2
at front right of fuel tank
Chapter
“
Separating plug-in connectors
”
.
On vehicles with auxiliary heater, detach fuel line
1
from hose
2
on metering pump
Rep. gr.
82
Fuel supply;
Removing and installing metering pump
V54
Remove rear silencer
Rep. gr.
26
Exhaust pipes/silencers; Removing and installing rear silencer
.
If fitted, remove heat shield.
Unbolt both shock absorbers on rear axle
arrow
.
Unhook breather lines
2
and
3
from rear final drive out of carrier plate
1
.
Remove carrier plate
1
.
Unscrew bolts
arrows
and lower fuel tank as far as propshaft.
Pull off both connectors on flanges.
WARNING
The fuel and the fuel lines in the fuel system can become very hot (danger of scalding)!
The fuel system is also under pressure! Before opening the system, place cloths around the connections. Then carefully loosen connection to release the pressure!
Wear eye and hand protection when performing any type of repair work on the fuel system!
Pull off fuel lines from both flanges
Chapter
“
Separating plug-in connectors
”
.
WARNING
Fuel tank is tilted to side during further work. To do this, fuel tank must be completely drained.
2nd chamber still full of fuel:
Loosen locking ring using
wrench
T10202
.
Lift up
fuel gauge sender 2
G169
.
Insert suction hose of
fuel extractor
VAS 5190
as far as possible into fuel tank and extract remaining fuel.
Fuel tank completely drained:
Pull off breather line on fuel tank and unclip from fuel tank.
Lower rear axle approximately 20 mm.
Open screw-type clip
3
and pull off connecting hose
4
wit filler neck from fuel tank
1
.
Unscrew bolts
arrows
and lower fuel tank
1
slightly.
Note
When lowering fuel tank, guide it carefully to prevent damage.
With fuel tank in position shown remove on left-hand side.
Installing
Install in reverse order. Note the following:
Caution
The fuel pump must not be allowed to run when the fuel tank is empty, as this may cause deflagrations.
The fuel tank must contain at least 5 litres of fuel.
When inserting fuel delivery unit, ensure that
fuel gauge sender 2
G169
is not bent.
Renew seal.
Insert seal for fuel delivery unit dry into opening of fuel tank.
Moisten seal with fuel only when installing fuel delivery unit.
Install breather and fuel lines free of kinks.
Do not interchange supply line and return line (return line blue or with blue marking, supply line black).
Ensure that line connections are tight.
After installing fuel delivery unit, check that the supply, return and breather lines are still clipped onto the fuel tank.
Check whether there are signs of oxidation on the earth wire of the connectors, remove if necessary.
Check installation position of earth connection.
Ensure that connector
2
is seated securely on metal ring
3
.
Contact tab
1
must be hooked into fuel tank
4
and secured by means of spacer bush
5
.
Check the connection of the metal ring on the fuel filler neck by measuring between the ring and a bare metal part of the body using an ohmmeter.
Specification: approx. 0 ohm.
If the specification is not attained, there is a risk of explosion due to electrostatic discharge.
Fill fuel tank with at least 5 litres of fuel.
Observe installation position of fuel supply line to supplementary heater
Auxiliary heater, supplementary heater
Rep. gr.
82
Fuel supply system
.
After installing fuel delivery unit, check that supply and return lines are still clipped onto fuel tank.
Specified torques
Fuel tank
Chapter
“
Assembly overview - fuel tank
”
.
Silencer with mountings and tunnel cross-piece
Rep. gr.
26
Exhaust pipes/silencers; Assembly overview - silencers
.