Timing Chain Tensioner: Description and Operation

Mounted in the cylinder head, the chain tensioner is easily accessible for service. Tensioning force is applied by a spring-loaded plunger which, via a guide bar pivoted at the bottom, keeps the slack side of the chain correctly tensioned. A ratchet with close-spaced teeth prevents the plunger, and with it the guide bar, from moving back.

Since the chain tensioner has close-spaced tensioning intervals, it provides good compensation for chain wear and consequently ensures quieter operation.