How to Check the Timing Chain in a 1998 Nissan Altima
- 1). Open the hood of the car and disconnect the battery negative cable. In the engine compartment, locate the distributor cap. The cap is located on the distributor shaft, which is connected to the camshaft. Use a screwdriver to remove the screws that secure it to the distributor shaft. With the cap removed, you will be able to see the distributor rotor.
- 2). Locate the crankshaft damper pulley (next to the camshaft) and attach a socket wrench to the pulley´s tensioner. Attach a degree wheel to the crankshaft damper pulley and begin rotating the tensioner with the socket wrench in a clockwise direction and observe the distributor rotor. Stop rotating the tensioner as soon as the rotor begins to turn.
- 3). Observe the degree marking on the degree wheel and then turn the tensioner in a counterclockwise direction. Keep your eyes on the rotor and stop rotating as soon as the rotor begins to turn. Observe the degree wheel to see how many degrees the crankshaft damper pulley has moved from the first rotation to the second. Fifteen or more degrees indicates that there is too much slack in the timing chain -- the ideal degree range for a healthy timing chain is 3 to 5 degrees. If your degree range falls under 10, but the timing chain makes a whirring sound, this indicates that the chain has jumped one of its teeth.
- 4). Remove the degree wheel and socket wrench from the crankshaft damper pulley and replace the distributor cap on the top of the distributor shaft. Use a socket wrench to reconnect the battery negative cable.
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