A reciprocating type gas compressor comprises a hollow frame or housing having spaced apart end walls, a motor-driven crankshaft disposed within the housing and rotatably mounted on bearing assemblies on the end walls and connecting rods connected to crank pins on the crankshaft for driving pistons located within the housing. The crankshaft comprises a drive shaft at one end and a pump shaft the other end, both extending along a common axis of rotation. The crankshaft also comprises a pair of axially spaced apart counterweights located between the two shafts and a crank arm or link located between the counterweights. A crank pin extends from each counterweight to the link along a pin axis which is parallel to and spaced apart from the common axis of rotation. Each bearing assembly has a hollow cylindrical inner race which is friction-fitted on a shaft at an end of the crankshaft and abutts the side of one counterweight. To enable removal of each friction-fitted bearing assembly from its shaft without damage thereto, a pair of threaded bores extend through portions of each counterweight and the bore axes are parallel to but located on opposite sides of the common axis of rotation and each bore is aligned with the inner end surface of the inner race of the associated bearing assembly. Each threaded bore accommodates a long jack screw which is temporarily rotatably inserted thereinto so as to engage the inner race and force the bearing assembly off of its shaft for servicing or replacement.