Abstract: Under generator axis supported on single side solid jointer must be used between two axises of diesel engine generator. Axis line difference between two axises is of great order concern to operation and life. The check of axis line difference between two axises is: at first jointer is checked, its cam-disk-cam construction must conform for centre, linking-up jointer must be firm and close, secondly the distance of curve hold arm near flying wheel is measured, that is in order to affirm deviation of direction and length, finally in accordance with the checked results it readjusts the position of single side bearing of generator in order to contrary readjusted direction to deviation direction, to equal in readjusted quantity to deviation quantity.