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Home >> Volkswagen >> 2002 >> Jetta GLI >> Repair and Diagnosis >> Engine Performance >> Ignition System >> 2.8L - Engine Mechanical, Engine Code: BDF >> 19 - Engine - Cooling System >> Cooling system components, servicing >> Cooling system components, servicing
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Cooling system components, servicing

CAUTION: When performing repair work, especially due to the confined conditions in the engine compartment, pay attention to the following:
  • Route all types of lines (e.g. for fuel, hydraulics, EVAP system, coolant, refrigerant, brake fluid and vacuum) as well as electrical wiring so that the original positions are restored.
  • Make sure sufficient clearance to all moving or hot components.
NOTE:
  • When the engine is warm the cooling system is under pressure. If necessary release pressure before commencing repair work.
  • Hoses are secured with spring-type clips. In cases of repair only use spring-type clips.
  • Assembly tool for spring-type clips VAS 5024 or hose clip pliers VAG 1921 are recommended for installing spring-type clips.
  • When installing coolant hoses route stress-free so that they do not come into contact with other components (observe markings on coolant connection and hose).
Fig 1: Identifying Assembly Tool VAS 5024
GW00000137Courtesy of VOLKSWAGEN UNITED STATES, INC.

Perform cooling system leakage test with cooling system tester VAG 1274 and adapter VAG 1274/8 and adapter VAG 1274/9.

Parts of cooling system, body side → Components of cooling system, body side  .

Parts of cooling system, engine side → Components of cooling system, engine side  .

Coolant hose connection diagram → Coolant hose connection diagram 

Disassembling and assembling coolant thermostat housing → Coolant thermostat housing, disassembling and assembling  .

Draining and filling coolant → Cooling system, draining and filling  .

Coolant mixing ratios → Cooling system, draining and filling  , Draining and filling coolant.