Method for refurbishing a valve seat in a fuel injector assembly
A method of refurbishing a fuel injector body valve seat. The method includes removing a poppet valve from the valve bore guide, machining the bore and valve seat to remove cavitation, machining to create an undercut a the stress riser, nitriding the valve bore guide and radiusing fuel passage to a sufficient depth to restore hardness thereto.
1. A method for refurbishing a fuel injector; said fuel injector having a body, a solenoid controlled poppet valve located in a valve bore guide in said body adapted to cooperatively engage a valve seat surface in said body; said bore intersecting a fuel passage at an angle to form a stress riser said method comprising:
removing said poppet valve from said valve bore guide;
machining said bore and valve seat to remove cavitation;
machining said fuel passage to increase a radius of the fuel passage with an undercut at said stress riser;
radiusing the fuel passage at said stress riser and undercut with abrasive flow technology;
nitriding said valve bore guide and radiused fuel passage to a sufficient depth to restore hardness thereto; and
inserting a poppet valve guide seat sleeve into said valve bore guide of a sufficient height to act as a valve seat.
2. The method of claim 1 , wherein creating an undercut and radiusing with abrasive flow technology creates a controlled radius of from about 0.7 mm to about 1.0 mm.