EMPLOYEES WERE PULLING ON THE WIRE RETAINING CABLE WHICH HOLDS DREDGE SUBMERSIBLE SVC PUMP, IN ORDER TO REMOVE PUMP, INJURED WAS ASSISTING BY PULLING PUMP. SUDDENLY PUMP CAME IN A RUSH AND HIT END OF MANIFOLD PIPE HOSE NIPPLE, CATCHING HIS INDEX FINGERTIP BETWEEN PUMP AND HOSE NIPPLE.