What was found
REPLACED PARTS RECEIVED BACK FROM OVERHAUL AGENCY FOLLOWING PROP STRIKE DISASSEMBLY INSPECTIONS, INCLUDED A PN SL-1024J PISTON AND SUBJECT NR 3 CYL INTAKE PIPE. PISTON EXHIBITED EARLY STAGES OF TYPICAL DETONATION DAMAGE ON THE HEAD, ADJACENT TO ITS O.D., AT THE 12 O'CLOCK POSITION AS INSTALLED. TPT 678 HRS. CAUSE APPARENTLY DUE TO EXCESSIVELY LEAN MIXTURES RESULTING FROM AMBIENT AIR ENTERING SUBJECT CRACKED INTAKE PIPE AND ADJ TO ITS CYL MATING END. CRACK WAS IN THE PIPE'S ATTACHMENT FLARE RADIUS, WAS CLEARLY VISIBLE, & EXTENDED AROUND APPROX 40 PERCENT OF THE PIPE'S DIAMETER. CYL HAD BEEN REPLACED 67 HRS PREVIOUSLY.