As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT EXHAUST STACK CRACKED. ENGINE WAS VIB CHECKED AND EXCESSIVE VIBRATION WAS DETECTED. UPON FURTHER INVESTIGATION, DETERMINED THE UPPER ENGINE MOUNTS WERE LOOSE ON AIRFRAME. NEW HILOCKS WERE INSTALLED ON ENGINE MOUNTS AND VIBRATION CHECK SHOWED VIBRATION AT ACCEPTABLE LEVELS. AIRCRAFT RELEASED FOR FLIGHT. REF: CONTROL NR 98-5-3.