Follow these steps and you should be fine although this is not an easy procedure.
- Disconnect negative battery cable.
- Using a wrench on crankshaft bolt rotate engine until timing mark on the crankshaft pulley is aligned with 0° mark on timing scale.
- Align distributor rotor with index mark on distributor housing indicating the rotor is in position to fire cylinder number one.
- Remove bolts holding timing cover in place, lift cover off engine.
- Check alignment of crank and camshaft timing marks.
- Loosen timing belt tensioner.
- Loosen mounting bolts holding the belt tensioner, but do not remove it.
- Pry tensioner away from belt and retighten mounting bolts to hold tensioner in loose position.
- Spin tensioner pulley and listen for rattle or humming noise that would indicate loose or worn bearings.
- With tension on timing belt relieved, belt should easily slide off sprockets. Timing belts that have been used for a long time may stick in pulley grooves and require gentle prying with a screwdriver to release.
- Slide new timing belt into position on sprockets.
- Loosen bolts holding timing belt tensioner and allow contact with belt.
- Proper timing belt tension is essential. Adjust timing belt to correct tension as outlined in your service manual.
- After belt tension is properly adjusted, verify timing marks on the cam, crank, and accessory sprockets are still in alignment.
- With a wrench on the crankshaft pulley, turn engine over by hand at least two complete revolutions in its normal direction of travel returning to the 0° mark. This will help seat new belt into place on sprockets.
- Verify position of all timing marks.
- Reinstall timing covers and tighten attaching bolts or screws securely.
- Reinstall components and drive belts that were removed to gain access to timing cover.
- Reconnect negative battery cable.
- Start engine and verify proper operation.