Timing Belts & Kits
The timing belts keep the engine in sync. After time, the belt and its components need to be replaced. Please check your service schedule to see when your replacement is due. The belt, rollers & tensioners should be checked periodically to ensure there is no damage or wear to the belt and that the rollers spin freely. If the cam belt fails the engine will have a catastrophic failure often resulting in bent or broken valves, snapped camshafts and damaged piston crowns. This is typical in an interference engine, which means the valve protrudes into the space where the piston reaches.
Trouble Chart - Timing belt automatic tensioner (Source: Dayco)
Metal contamination and oxidation
Causes:
- Contact with contaminating components: oil, dust, leakage of coolant
Actions:
- remove leakage of coolant
- remove leakage of oil and/or fuel
- replace the faulty/damaged component
Broken central pin
Causes:
- Incorrect setting of the bolt: the torque applied is higher than the value specified on the maintenance sheet.
Actions:
- apply the correct tightening torque
- use the torque wrench
- replace the faulty/damaged component
Broken Stop Contact
Causes:
- Incorrect setting of the tensioner: "excessive unload" condition with the belt excessively slack in the transmission
- Incorrect setting of the tensioner: "excessive load" condition with the belt tensioned in the transmission.
Actions:
- replace the components when the engine is cold
- apply the correct tension to the belt
- check the alignment of the reference indexes
- check the belt tension after the adjustment turns
- use the tensiometer to check the belt tension
- replace the faulty/damaged component
Broken stop contact / Dents on the end stop
Causes:
- Incorrect setting of the tensioner with loss of capacity to modulate and compensate the belt tension variations
Actions:
- replace the components when the engine is cold
- apply the correct tension to the belt
- check the alignment of the tensioner reference indexes
- check the belt tension after the adjustment turns
- replace the faulty/damaged component
Timing Chain Kits
Chains generally have a longer service life than belts, but chains and their components need to be checked regularly. Servicing is critical to the operation of the chain. Often, the chain tensioner works under oil pressure. If the oil is low or insufficient oil reaches the tensioner, the chain will run without enough tension which can damage guide rails and sprockets.
