volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

Coolant pump, thermostat, coolant pipes > < Draining and filling coolant
Checking cooling system for leaks
Checking cooling system for leaks
Special tools and workshop equipment required
   
t  Cooling system tester -V.A.G 1274 B-
  W00-10657
t  Adapter for cooling system tester -V.A.G 1274/8-
  W00-0703
t  Adapter for cooling system tester -V.A.G 1274/9-
Test prerequisite
l  Engine at normal operating temperature
Test sequence:
  WARNING
When the engine is warm, the cooling system is under pressure.
Hot steam/hot coolant can escape - risk of scalding.
Cover filler cap on expansion tank with a cloth and open carefully to dissipate pressure.
–  Open cap on coolant expansion tank.
–  Screw adapter for cooling system tester -V.A.G 1274/8- onto expansion tank.
–  Clamp connector -V.A.G 1274 B/1- into adapter for cooling system tester -V.A.G 1274/8-.
  W00-0564
–  Join connection piece -V.A.G 1274 B/1- to cooling system tester -V.A.G 1274 B- using connecting hose supplied.
–  Use hand pump on tester to create a pressure of about 1.0 bar.
  DANGER!
Risk of scalding! Before disconnecting cooling system tester -V.A.G 1274 B- from connecting hose or connector -V.A.G 1274 B/1-, relieve existing pressure under all circumstances. To do this, press pressure relief valve on cooling system tester -V.A.G 1274 B- until pressure gauge displays value of »0«.
If pressure drops:
–  Find leaks and rectify.
Checking pressure relief valve in filler cap:
–  Screw cap into adapter for cooling system tester -V.A.G 1274/9-.
–  Clamp connector -V.A.G 1274 B/1- into adapter for cooling system tester -V.A.G 1274/9-.
  A19-10645
–  Join connection piece -V.A.G 1274 B/1- to cooling system tester -V.A.G 1274 B- using connecting hose supplied.
–  Operate hand pump.
l  The pressure relief valve should open at a pressure of 1.4 …1.6 bar.
  A19-10748

Coolant pump, thermostat, coolant pipes > < Draining and filling coolant