volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

ABOUT US
Removing and installing tandem pump > < Checking delivery pressure

Golf Mk5

Checking for internal leaks
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 renewing 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
   
t  Tester -V.A.G 1687-
Procedure
–  Pull fuel supply hose (white marking) and fuel return hose (blue marking) off tandem pump.
–  Seal fuel return union on tandem pump with a plug. Secure sealing plug with a spring-type clip.
Prepare test unit -V.A.G 1687- as follows:
–  Unscrew pressure regulating valve -2- and close valves -3- and -4-.
  W00-10327
–  Connect test connection -5- to fuel supply union of tandem pump using a commercially available compressed air connection and a section of fuel hose. Use a spring-type clip to secure.
  Note
To turn the pressure regulating valve -2- the knob must be pulled upwards.
  V21-0168
–  Connect compressed air hose -1- (compressed air source) to charge air system tester -V.A.G 1687-.
  Note
If there is water in the sight glass, drain at water drain screw -6-.
–  Open valve -3-.
–  Adjust pressure to 1.0 bar with pressure regulating valve -2-.
  Caution
The maximum test pressure is 1.3 bar and this must not be exceeded.
–  Open valve -4- and wait until the test circuit is filled. If necessary readjust pressure to 1.0 bar.
–  Close valve -3- to retain pressure and observe the pressure drop over a period of 1 minute.
If the pressure does not drop the tandem pump can be reused, if the pressure drops the tandem pump must be renewed.
  V21-0168

Removing and installing tandem pump > < Checking delivery pressure