How to change a Timing Belt/Cam Belt

by Andrew Automoto2. January 2014 09:59

If you wish to to change your Timing Belt/Cam Belt here are 28 steps...it is also recommended you change the water pump at the same time as your timing belt.

Tools you may need:

  Combination Wrenches , A key Set , Torque Wrench, A Harmonic Balancer Puller, A Three-jaw Gear Puller, Screwdrivers, Timing Light, Timing Belt Cover Gasket Set, New Timing Belt, Drain Pan, Antifreeze, Jack, Jack stands

(Some models may require special tools)

Now Let's get started:

  1. Disconnect the negative battery cable. (make sure you have your radio security code as this will disconnect the radio as well)
  2. Remove the distributor cap. Modern vehicles with an electronic ignition will have a cam position sensor instead. It is important to be able to determine the ‘TDC” (top dead centre) on the number 1 cylinder.
  3. Using a wrench or socket on the crankshaft bolt rotate the engine until the timing mark on the crankshaft pulley is aligned with the 0 mark on the timing scale. Under any circumstances do not do this on Interference engines unless you are sure the timing belt is still intact.
  4. Make sure the distributor rotor is aligned with the index mark on the distributor housing, this will indicate that the rotor is in a position to fire the number 1 cylinder. If it’s not on the index mark rotate the engine another full turn.
  5. Remove any components or drive part accessories that may interfere when trying to remove the timing belt.
  6. Remove the bolts or screws holding the timing cover in place and lift the cover off the engine.
  7. Check for the proper alignment of the crank and camshaft timing marks. Most engines have a dot or index line on the pulleys and sprockets that must be lined up marks on the block, cylinder head or accessory shaft. Make sure you consult your service manual for the correct alignment procedure. This is very important to get right.
  8. Check the area around the belt for signs of oil leakage from the cam and crank seals, valve cover and oil pan. Also check for coolant leaks from the water pump and water pump by-pass hose. All leaks must be repaired before the new belt is installed.
  9. Loosen the timing belt tensioner – some vehicles may require a special tool to reach the tensioner mounting bolts. Some engines require a special tool to release the spring-loaded timing belt tensioner, however most engines have a spring-loaded tensioner that can be loosened using common tools as follows.
  10. Loosen the mounting bolts holding the belt tensioner. DO Not Remove.
  11. Pry the tensioner away from the belt and re-tighten the mounting bolts to hold the tensioner in a loose position.
  12. Check the tensioner pulley for damage such as dents or cracks.
  13. Spin the tensioner pulley and listen for a rattle or humming noise that indicate loose or work bearings. Uneven wear at the end of an old timing belt could indicate a misalignment between the tension pulley and the timing belt due to worn bearings.
  14. Replace the worn or loose bearings, then replace the tensioner pulley.
  15. DO NOT ROTATE THE CRANKSHAFT OR CAMSHAFT AFTER REMOVING THE TIMING BELT- Unless you need to correct a timing mark misalignment.
  16. With the tension on the timing belt relieved the belt should slide of the sprockets easily. If the timing belt is old it may stick in the pulley grooves, gently pry the timing belt with a screw driver.
  17. Make sure to compare the old belt with the new timing belt to make sure the shape and the belt teeth, and spacing are the same.
  18. Slide the new timing belt into position on the sprockets. – Do not force the timing belt over the sprockets, if the belt won’t slide easily check to make sure the belt tensioner is fully released.
  19. Loosen the bolts holding the timing belt tensioner and allow it to make contact with the new belt.
  20. Adjust the timing belt to the correct tension following the procedure for your specific vehicle outlined in the service manual.
  21. After the belt tension is properly adjusted, confirm the timing marks on the cam, crank and accessory sprockets are still in alignment.
  22. With a  wrench on the crankshaft pulley, turn the engine over by hand at least two complete turns, so it’s in its normal direction of travel returning it to the 0 mark.
  23. Make sure there is no contact with the valves or pistons on interference engines.
  24. Verify the position of all timing marks
  25. Reinstall the timing covers and tighten all the bolts securely.
  26. Reinstall the components and drive belts that were removed to gain access to the timing cover.
  27. Reconnect the negative battery cable.
  28. Start the engine and verify the proper operation. 
     It is recommended that a licensed mechanic change your timing belt. If you do not have the tools listed, or do not understand the instructions it is recommended you do not attempt to change the timing belt in your vehicle.
     For further assistance please visit one of our licensed service centres on www.carservice.com.au

     For more information on how Timing Belts see - Timing Belts/Cam Belts
     For more information on water pumps see - How to change a Water Pump.
 

‘The information provided in this article is for general advise only.  It is not intended for instructional use.  Use of the information is at your own risk.  We recommend you seek the advice of a trained professional.'