[john walker's workshop]

If you can compress it by hand, the check ball is not seating properly, or the lower chamber has air in it. To bleed the lower chamber, you fill the upper chamber with oil, insert a key tag wire into one of two holes in the piston to dislodge the check ball and slowly pump the piston so oil gets sucked into the lower chamber. Pull out the wire and test for squishyness. Should have none. Fill the upper chamber, open the bleed screw a bit, tilt the tensioner so the screw is angled upward, squeeze in the top aluminum disc until air bubbles stop coming out the bleeder screw, but don't bottom it out. Close the screw. Assemble the tin cap, spring and clip.