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Thermostat Valve Replacement

Model: Volkswagen Golf Golf IV, Golf 4, MK 4 - Years: 1997, 1998, 1999, 2000, 2001, 2002, 2003
Part: Thermostat

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Video tutorial

To access the thermostat valve, remove the alternator. Before removing the auxiliary belt, remember or note the routing of the belt around the various pulleys; then loosen the tensioner with a 16 mm spanner and remove the belt.

At this point, unscrew the alternator mounting bolts and disconnect the connector and the cable attached to it. Next, remove the tensioner to access the other alternator mounting bolt for complete removal. Once the alternator is out, you can access the hose containing the thermostat valve, located just behind the alternator mounting plate.

Unscrew the two screws securing the plastic hose and extract the thermostat valve to replace it with a new one. Then proceed in reverse order for reassembly, securing the alternator first and then the tensioner.


Updated on 7 February 2026 by ScegliAuto


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