JIMS, crankcase lap tool

Used to lap pinion bearing race in the right crankcase. Removes more material in less time but with greater accuracy than a conventional lap. The JIMS case lap is guided on both sides of the pinion bearing race. This additional support on the cam gear side of the bearing race is achieved by means of a bolt on the base plate that precisely locates a drill bushing in which the lap turns. This base plate is located on the same engine case pins as the cam cover. The positioning of this drill bushing is held within .0002" to the engine case pins and within .0002" of the case centerline.