Cessna/ Texton has issued the following service bulletin related to fuel pumps.

TITLE
FUEL – INSPECTION OF 5100-00-4 ELECTRIC FUEL PUMP
EFFECTIVITY
Group A Airplanes:
The following airplanes were delivered with an 5100-00-4 Electric Fuel Pump with a serial number in the suspect range identified in this service document:

MODEL SERIAL NUMBERS
172S 172S12129 thru 172S12182

Group B Airplanes:
The following airplanes if the 5100-00-4 Electronic Fuel Pump has been installed as spares between October 1, 2017 and the date of receipt of this service document:

MODEL SERIAL NUMBERS
172R 17280001 and On
172S 172S8001 and On
182S 18280001 thru 18280944
NOTE: Also affected are fuel pumps received in Authorized Service Facility stock.

REASON
Some fuel pumps have been identified to have incorrectly installed seal and possible FOD that can cause pump vanes to stick or not pump correctly and must be replaced. A pump with an incorrectly installed seal does not meet engineering design and a pump with FOD can make a grinding noise during operation or fail to pump fuel. During a flight situation where the auxiliary electric fuel pump is required to provide fuel to the engine, a pump that is not pumping correctly or stops pumping fuel, can cause a total loss of engine power.

DESCRIPTION
This service document provides parts and instructions to inspect the maintenance records for suspect fuel pump serial numbers and replace the fuel pump if a suspect fuel pump is installed.

NOTE: Fuel pumps that have a serial number with an “R” suffix have been reworked by the manufacture and are acceptable for use. It is not necessary to replace a fuel pump that has a serial number with an “R” suffix.

Read the entire PDF here.