It took a while with a back-up WIN98 computer to get the site to accept it, but here is a photo of the system of tools that are required when a pump is badly damaged, or of a metal so "chilled" that only grinding will produce an accurate surface.
The years of applying the standard burnisher, as shown at the far right, to modern aluminum pumps gave me a false sense of security on the earlier productions, and I deeply regret ever encouraging the use of a burnisher on an installed pump.
Only on the bench, and with optical enhancement for inspection, can a quality seat be assured.
The stones pictured have all been reduced in diameter to just clear the cap threads in the pump bodies.
Piloted as shown on the far left, the top of the seat is taken down with a 90 degree stone, much as a motorvalve in a cylinderhead would be.
The course and fine stones next to it are dressed to an arbitrary 60 degrees, as is the conical burnisher.
The finish of the burnishers must be of a high luster to produce a perfect seal, and I found a few castings that blemished the ball immediately, for lack of malleability. Ordinarily, the ball remained effective for several pumps, and a polish would put them back into service.
Further complications arose when original seats were not drilled concentric to the cap threads that I so diligently attempted to use for my pilots.
It turns out that the sloppier the burnisher, the better.
I have already lost enormous R&D energy on this problem,
and have reaped mostly embarrassment.
But I encourage anyone who sees the importance of this problem to pick up the ball and run with it.
Dumpster Diver's Motto: Seek,... and Ye Shall Find!