This hydraulic demolition hammer, as a general rule, should be used with the same technique as a jackhammer. Choose the appropriate tool in order to obtainThis comprehensive operator's manual contains instructions for operating and maintaining NPK HYDRAULIC HAMMERS. This manual includes helpful information for. Find many great new & used options and get the best deals for Rockram 778 Hydraulic Hammer Breaker Maintenance Shop Service Repair Part Manual at the best Rockram / Ramco 773 Hydraulic Hammer Parts & Tool Bits ; DESCRIPTION; PART ; UPPER HEAD 773; 1 ; HELICOIL THREAD 773; 1 ; POLY. DIAPHRAGM 773; 2 ; ACCUMULATOR, Description: Replacement tool for ROCKRAM 770 / 778 hammer. Your price: Call for Best Pricing! Stand the hydraulic hammer vertically on the demolition tool and apply contact pressure. This ensures that the tool is positioned in the maximum upward lo-.