Patent ID: 8046917

Claim:
A method for refurbishing a valve seat in a fuel injector module housing with a valve seat of larger diameter than an associated valve guide bore, comprising: inserting an indexable lapping insert into said valve guide bore, said insert having inclined top and bottom surfaces coated with an abrasive to form lapping surfaces; said top and bottom separated by a side wall extending substantially unbroken therebetween; said side wall comprised of two opposed flats of equal length intersecting two opposed arcs of equal length, wherein the inserting comprises orienting the lapping insert into the valve guide bore by rotational movement of said insert by a spindle; said insert having an opening extending perpendicular through said body adapted for mating engagement with the spindle; driving the spindle to cause the insert to lap the valve seat; and removing the insert from valve guide bore when lapping of the valve seat is complete.