Service difficulty report · Oil Ring · Mooney M20J

Difficulty date
October 28, 2003
Submitted
November 17, 2003
Operation
General aviation
Aircraft
N923DH
Make and model
Mooney M20J
Aircraft serial
243368
Engine
Lyc IO360A3B6
Part
Oil Ring
Part number
14H21950
Condition
Broken
Location
Nr 3 Cylinder
Part time
1,136 hours
Stage of operation
NR
How discovered
O
Nature of condition
R, J
Precautionary procedure
A

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

AIRCRAFT WAS IN FLIGHT WHEN THE PILOT NOTICED HIGH CHT TEMPS AND LOW EGT TEMPS ON NR 3 CYLINDER ON HIS JPI ENGINE ANALYZER. HE THEN NOTICED HIS OIL TEMP GO UP AND AS THE OIL PRESSURE DROPPED THE OIL TEMP THEN BEGAN TO DROP OFF. HE THEN PULLED THE POWER OFF AND LANDED THE AIRCRAFT. 2-3 QUARTS OF OIL WERE STILL REMAINING IN THE ENGINE. COMPRESSION CHECKS WERE NORMAL BUT NR 3 CYLINDER WAS REMOVED TO FIND THE OIL CONTROL RING PN 14H21950 TO BE BROKEN AND SEIZED INTO THE PISTON. COMPRESSION RINGS WERE STILL INTACT. CONNECTING ROD BUSHINGS WERE FINE, VISUAL INSPECTION OF INSIDE OF ENGINE ACCESSIBLE THROUGH THE REMOVED CYLINDER OPENING APPEARED NORMAL.

More about the Mooney M20J