This pilot/owner describes climbing past 4,000 feet when the right engine on this Piper Comanche “...shuttered and began vibrating excessively.” A safe return to the airport was followed by a relevant inspection. The camshaft (P/N AEL18840) was found broken into two pieces. The engine’s total time since overhaul: 100 hours. No speculation for this camshaft failure was provided.

(The submitter included a copy of the FAA Form 8130-3, Authorized Release Certificate showing the camshaft to be new at time of installation.)

Part Total Time: 100 hours.