How to Replace a Fan Belt on a Mercedes 190D
- 1). Open the hood for access to the engine compartment. Locate the tensioner pulley between the distributor and the power steering pump, near the center of the engine.
- 2). Loosen the larger bolt on the tensioner pulley with a socket wrench. This will unlock the tensioner pulley.
- 3). Loosen the smaller nut on the tensioner pulley with a socket wrench. This will loosen the tension on the belt.
- 4). Remove the belt from the pulleys and replace it with a new belt.
- 5). Route the new belt around the pulley. Follow the diagram printed near the radiator, which shows the correct belt path.
- 6). Tighten the smaller nut with the socket wrench. This will place the tension on the belt.
- 7). Tighten the larger nut with the socket wrench. This will lock the tensioner.
- 8). Feel the belt to ensure there's no slack. Start the car to make sure there is no lag in the belt as it runs across the pulleys.
- 9). Turn the car off. Close the hood.
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