A torque converter having three sealed chambers in which a piston for engaging and disengaging a lock-up clutch is attached to the torque converter using a plurality of leaf springs. The assembly includes a plurality of access or pass-through holes for effecting the attachment of the leaf spring to the cover using rivets. Also included is plurality of plugs to seal the pass-through holes. A method of using the plugs to prevent uncontrolled leakage from one sealed chamber to another.