There are two installation options for the timing chain tensioner - install activated.or unactivated.
Most of the guys on the forum recommend fitting them activated which ensures the tensioner is functioning correctly. This is done by closing the tensioner up with a screwdriver then tapping it sharply on a solid surface to 'activate' the spring load, then screw into the cylinder head (there is more pressure than normal required) and torque up.
To install unactivated, screw the tensioner into the head and torque up, then by inserting a solid bar in the opening of the cylinder head (camshaft sprocket end) and pressing against the chain and rear guide rail the tensioner can be activated, however this is not as reliable as fitting it activated.