Volkswagen Fox 2004 Workshop Manual page 103

– Install auxiliary pump and tighten upper securing bolts to 20
Nm.
– Tighten lower securing bolts to 10 Nm.
– Fit supply pipe -2- (white marking) to auxiliary pump supply
connection and vacuum hose -1- from servo-assisted brake to
the auxiliary pump -4-.
– Connect pipe -1- (white marking) to fuel filter.
– Connect the Vacuum pump -VAG 1390- with the Fluid con‐
tainer -VAG 1390/1 - to return pipe.
– Activate Vacuum pump -VAG 1390- until no more fuel comes
from the return pipe. Take care not to suck fuel into the vaccum
pump.
– Fit return pipe -2- (blue marked) in the fuel filter.
1.11.3 Checking for internal leaks
Note
The tandem pump must be checked for internal leaks between
fuel side and oil side after reinstalling a used tandem pump, for
example after replacing or repairing a cylinder head and/or when
installing a "short" engine. When leaking it is possible for the fuel
to mix with the oil which may cause the engine to fail.
Special tools and workshop equipment required
♦ Tester -V.A.G 1687-
Procedure
– Pull fuel supply hose (white marking)
fuel return hose (blue marking)
pump.
– Seal fuel return union on tandem pump with a plug. Secure
sealing plug with a spring-type clamp.
Prepare test unit -V.A.G 1687- as follows:
⇒ Item 28 (page 39)
⇒ Item 29 (page 39) off tandem
3 - Cyl. diesel engine - Edition 02.2009
and
1. Fuel supply system components - remove and install
Fox 2004 ➤
99