Service difficulty report · Lock Nut · Waco UBF

Difficulty date
September 15, 2015
Submitted
November 6, 2015
Operation
General aviation
Aircraft
N13444
Make and model
Waco UBF
Aircraft serial
3763
Engine
Cont W670*
Part
Lock Nut
Condition
Broken
Stage of operation
NR
How discovered
9
Nature of condition
O
Precautionary procedure
O

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

What was found

ON REMOVING THE REAR CASE OF THIS ENGINE, FOUND Y BROKEN .3125 LOCK NUTS. ALSO FOUND 3 BROKEN NUTS ON THE OIL PUMP WHICH IS ATTACHED TOTHE REAR CASE SOME OF THOSE NUTS WERE BROKEN IN 3 SECTIONS. THE ENGINE WAS O/H.

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