As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON INSTALLING AN OVERHAULED CYLINDER, NOTED THE CYLINDER WAS NOT ALIGNED WITH THE ONE NEXT TO IT AT THE ROCKER BOX AREA. THE SHORTEST PUSH ROD WOULD NOT GO IN. IT WAS FOUND OUT THAT THE CYLINDER WAS TOO SHORT AFTER OVERHAUL. ANOTHER CYLINDER WAS PUT ON AND IT WORKED OK. THE CYLINDER THAT WAS TOO SHORT HAD A SERVICEABLE TAG.