How to Change the Alternator Belt on a 1990 Nissan 240SX
- 1). Open the hood and secure it in place.
- 2). Remove the front belt by locating the adjustment pulley that holds the front belt tight inside of the pulleys. The adjustment pulley has a locking bolt on the front and an adjustment bolt on the end of the pulley.
- 3). Loosen the locking bolt with the 3/8-inch ratchet and a socket. Turn the adjustment bolt at the end of the pulley counter clockwise to release the tension on the front belt. Pull the front belt off and set it to the side.
- 4). Locate the adjustment bracket on top of the alternator. Loosen the locking bolt on the adjustment bracket with the 3/8-inch drive ratchet and a socket. Then, turn the adjustment bolt on the end of the adjustment bracket counterclockwise with the 3/8-inch drive ratchet and a socket. Pull the belt off and set it to the side.
- 5). Route the new alternator belt around the alternator pulley and the crankshaft pulley. Turn the adjustment bolt clockwise to tighten the belt with the ratchet and socket. Then, tighten the locking bolt on the front of the alternator bracket down tight with the ratchet and socket.
- 6). Put the front belt back on the pulleys. Turn the adjustment bolt on the end of the adjustment pulley clockwise with the ratchet and socket to tighten the front belt. Then, tighten the locking bolt on the front of the pulley down tight with the ratchet and socket.
- 7). Crank the 1990 Nissan 240SX and let the engine run for about one minute. Then, turn off the engine. Inspect the belts again to ensure that they have remained inside of the pulleys. Close the hood.
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