Continental IO-360-ES piston.
Note the scoring on the skirt area.The very high piston temperature had caused the piston to expand so much that it was seizing in the cylinder bore. This caused the burn marks shown on the photo below.
In this case the steel insert has limited melted area of the piston, but the damage has already been done.
Piston damaged by a pre-ignition event.
We never been able to work our what caused this magneto from a Piper Chieftain to fail in the manner that it did.
Any oil leak can be disastrous
Excessive main bearing clearances lead to poor oil flow to this connecting rod bearing. Very lucky that the connecting rod did not separate and cause an in flight engine stoppage.
In flight oil leaks are insidious, as the oil pressure remains relatively normal until the oil level in the sump has dropped to the level of oil pump pickup. Once the oil pump starts sucking air, oil pressure is quickly lost, followed shortly thereafter by a major engine failure. Without oil pressure, connecting rods will make their way out of the crankcase.
Debris in the sump after a major engine failure.
A bent connecting rod from a Continental TSIO-520-E engine in a Cessna 402.
Over-priming caused a Hydraulic Lock and the bent connecting rod.
Main Bearing insert from a Continental IO-360-G.
A bad hair day for a Continental Starter Adapter.
If excessive friction in the starter motor does not allow the clutch spring to fully release, this can happen.
Transfer collars in Continental engines need to be lubricated at all times.
When installing a new engine or changing a propeller governor, priming the oil gallery to the transfer collar with clean engine oil is good practice.