Belts are primarily used on overhead camshaft engines. Always follow manufacturer’s recommendations regarding cam belt change intervals and replacement procedures. The objective of this procedure is to show you how to safely remove and replace a cam belt.
Step One
Personal safety - Whenever you perform a task in the workshop you must use personal protective clothing and equipment that is appropriate for the task and which conforms to your local safety regulations and policies. Among other items, this may include: Work clothing - such as coveralls and steel-capped footwear. Eye protection - such as safety glasses and face masks. Ear protection - such as earmuffs and earplugs. Hand protection - such as rubber gloves and barrier cream. Respiratory equipment - such as face masks and valved respirators. If you are not certain what is appropriate or required, ask your supervisor.
Step Two
Disconnect the battery - Locate the battery and its negative terminal. Loosen the terminal clamp and remove the terminal from the battery post. Store the terminal so it cannot come in contact with the battery post.
Step Three
Remove drive belts and cover - Remove any drive belts located at the front of the engine to gain full access to the timing belt cover. Turn the engine by hand to top dead center for number 1 cylinder firing. Loosen and remove the front pulley attached to the crankshaft. Loosen the fasteners that locate the timing belt cover and remove it.
Step Four
Remove the timing belt - Loosen the belt tensioner and pry it away from the belt and retighten the fastener to prevent it from springing back and placing tension on the belt. Remove the timing belt.
Step Five
Fit timing belt - Place the belt over the pulleys and position it correctly. Make sure that the crankshaft is still at top dead center and the camshaft aligning marks are correctly aligned. Manufacturers service manuals normally have a diagram to follow.
Step Six
Adjust tensioner - Slowly loosen the fastener that secures the belt tensioner and allow it to slide gently back against the cam belt. Turn the engine by hand in the direction of normal rotation for at least two complete turns to allow the tensioner to find its correct tension. Lightly tighten the fastener so it cannot move.
Step Seven
Check the timing marks - Reposition the engine at top dead center for number one cylinder firing, and check that the location of all the timing marks are still in accordance with the manufacturers directions. Now tighten the tensioner-securing fastener to the recommended torque.
Step Eight
Refit timing cover - Replace the timing cover and refit any fasteners. Refit the front pulley and tension to the correct torque, and replace any ancillary drive belts to drive ancillary equipment in accordance with vehicle specifications.
Step Nine
Start engine - Start the engine and check for correct operation.