As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE COMPLYING WITH LYCOMING SB 518, FOUND VALVE ASSEMBLY LOOSE IN VALVE HOUSING. SNAP RING GROOVE IN VALVE WORN OUT. FOUND SEVERE NICKS IN RETURN SPRING AND BELLOWS. NICKS APPEAR TO BE CAUSED BY EXCESSIVE SIDE MOVEMENT DUE TO LOOSE SNAP RING GROOVE.