|PART 21 - EMD FUEL INJECTORS SEIZED PLUNGER AND BUSHING
The following is a summary of information that was received via facsimile:
Engine Systems, Inc. (ESI) was notified by a nuclear customer that three of 20 recently installed fuel injectors seized after a short amount of engine run time. Examination of the plunger and bushing (P&B) from each injector identified particles consistent with the base material of the P&B embedded in the scar marks associated with seizures. The root cause of the seizures is attributed to residual machining debris from the manufacturing process. This batch of injectors had been refurbished in 2013 and the P&Bs were replaced as part of the rework activity.
These part number mechanical unit fuel injectors are used on various model EMD 645 diesel engines. The engine utilizes one injector per cylinder; therefore, failure of one injector will render the associated cylinder inoperable. An EMD 645 engine will typically tolerate one inoperable cylinder and maintain rated load; however, multiple inoperable cylinders (as in the case of multiple fuel injectors) will further decrease engine output and likely prevent the engine from carrying out its required load. This adversely affects the ability of the emergency diesel generator set to perform its safety-related function.
This issue only applies to injectors in inventory that have not been installed, which should be returned to ESI. For injectors that have been installed in an engine and have accumulated more than two hours of run time, then the injector is not susceptible to seizure from this type of issue and no further action is required. It has been shown that P&B seizures related to foreign material occur within the first two hours of engine operation.
The affected part numbers are 40084714, 40084715, 40084720, 40084724, 40084725, 40099335, 5228895-RR, 5229250-RR, 5229315-RR, 5229325-RR, 40084714-RR, 40084720-RR, 40084723-RR, 40084724-RR, 40099335-RR. A list of affected customers by injector part number is contained in Appendix A of the Part 21 report, which include Crystal River, Turkey Point, Exelon Generation Company, Beaver Valley, Watts Bar, Clinton, Saint Lucie, Sequoyah, Cooper, Southern California Edison, Davis-Besse, Oconee, Point Beach, Kewaunee, Dresden, Surry, GE Company, Browns Ferry, Energy Northwest, Oyster Creek, Arkansas Nuclear One, Monticello, Nine Mile Point, Entergy Operations Inc., Tennessee Valley Authority, LaSalle, Perry, Quad Cities, Fitzpatrick, and River Bend.