I live in an area of machine shops with MSC store in the center. Most of the shops are all CNC high production shops for aerospace industry.In fact I saw on sixty minutes there are lots of machine shop jobs out there, but the younger crowd do not want to do this job. They would rather have a "facebook" type job. The classic hand crank machine shop is difficult to find. Really do not know what other folks are doing and have searched the archives with no results on this oil pump bushing issue. Surely not everyone is doing the co-axial indicator method on a vertical mill, which appears to be the high end setup. Mercury marine shop manual includes this lapping procedure to condition rod wrist pin bushing. The hand held spindle will find its own center, if the contract pressure from the abrasive cloth is uniform. This method might be OK if only .001" to .002" material removal is required. Sanded one end of the split bushing to make a champher. It pressed into the cap without any scraping. Then realized that 50% of the bushing wall was going to have to be removed to make it fit the gear pump shaft. Forget hand held abrasive cloth lapping method as mentioned previously for this much material. Ths oil pump bushing thing is one of the most difficult procedures of the engine rebuild in my opinion. Like I said before the automotive machine shop used the specialized machine built for doing rod wrist pin bushings using a stone hone to hone the pump shaft bushing to size. Believe this machine is supposed to follow the center of the bushing. The bushing was honed orthonical to the cap face, however. Anyway the bushing was not honed concentric and was offset towards the driven gear shaft.
Now the gear teeth will have to lap themselves, since there is noticable sliding friction when aluminum gear is rotated by hand, but does rotate and is not locked up. Is it possible to get an adjustable reamer that is 1/2" nominal diameter?
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