The Mystery of Missing Barrel Teeth

   These parts belong to a Kawasaki K5V80DTP pump, which dished out almost 20,000 hours before ending up on my "operation table". Apparently, the machine stopped when the teeth inside one of the barrels disappeared.

   Now - for the mystery part: we witness quite a lot of steel missing here - the cylinder block one lost the teeth completely, the cylinder block two has maybe slim 25 percent of teeth left, also the respective splines on both of the shafts present extensive wear, and the shaft end bearing surfaces are all pitted and warn out - in other words plenty of iron had to be grinded to dust before coming to this point, yet there isn't much wear in other parts of the rotary groups. The piston shoes and the thrust plates look almost new with but minor scratches, the valve plates and the cylinder blocks have traces of small particle wear, but again - with no noticeable difference in height between the marked and not marked areas - something you would naturally expect from a 20,000 hour old rotary group.

    My theory - the oil and the filters were changed at regular intervals, but no scheduled overhauls of the pump were ever performed. The result was a relatively long life of the unit, which still ended abruptly and unexpectedly when the parts that wear out, well, wore out...