How to Replace a Timing Belt in a Jetta 1.8T
- 1). Disconnect the negative battery cable and lay it aside, ensuring that it does not touch metal. Loosen the tensioners on the accessory drive belts. If the tensioner is a slider, loosen the lock bolts, then the slider bolts and slide the accessory toward the engine. If the tensioner has a pulley, use a wrench or socket to rotate the pulley away from the belt, thus relieving the tension on the belt. Lift the belts off the pulleys.
- 2). Remove the upper timing belt cover using the appropriate socket. Turn the crankshaft clockwise until the timing marks on the AT models are lined up at the 12 o’clock position. For MT models, the timing marks are located on the flywheel. Check the camshaft timing marks. If they are not lined up at the 12 o’clock position, turn the crankshaft one more turn and both timing marks will line up.
- 3). Remove the crankshaft pulley bolts, the crankshaft pulley and the lower timing belt cover using the appropriate sockets. Loosen the timing belt tensioner pulley nut. Turn the tensioner pulley counterclockwise, using the 2-pin wrench, to relieve the tension on the belt. Lift the belt off the sprockets and pulleys. Check that the timing marks are still lined up.
- 4). Reinstall the lower timing belt cover temporarily. Make sure the timing marks are still lined up (on the crankshaft for AT models; on the flywheel for MT models). Install the timing belt, starting on the crankshaft sprocket. Keeping it taut as you work, route it around the intermediate shaft sprocket and over the top of the camshaft. Route it behind the tensioner. The belt will be loose on the tensioner side.
- 5). Set the tension gauge to zero, then hook it on the timing belt halfway between the camshaft sprocket and the intermediate shaft sprocket. Turn the tensioner pulley clockwise using the 2-pin wrench until the gauge reads 13 to 14 units.
- 6). Tighten the tensioner pulley nut to 33 foot-pounds of torque. Remove the tension gauge. Turn the crankshaft clockwise two turns until the timing marks line up again. Recheck the tension in the same spot on the belt, using the tension gauge. Adjust the tension if necessary. Install the rest of the parts in reverse order of removal. Make sure the timing marks on the crankshaft on AT models are lined up. Tighten the crankshaft pulley bolts to 15 foot-pounds of torque.
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