Abstract

A ratcheting tensioning device for a closed loop chain driven power transmission system of an internal combustion engine consisting of a base tensioner arm (12) and an adjusting tensioner arm (14) which each contact different strands or chain. Optionally, each arm may have a chain guide element for contacting the chain. The two tensioner arms (12, 14) are connected by a link plate (16) that is pivotally mounted to the base tensioner arm (12) in proximity to a first edge (24) of the link plate (16). A channel (52) located in proximity to a second edge (25) of the link plate (16) which allows a pin or sleeved bolt, to be securely attached to the adjusting tensioner arm (14), to traverse along the length of the channel (52) to urge the two tensioner arms (12, 14) toward each other in response to progressively increasing slack in the chain caused by the wearing over time of the components of the power transmission system.