PLUG AS 9T3928 - Caterpillar

Do not disconnect any oil lines from the valve until all oil pressure in the main system has been released.
1. Remove oil line (1), then disconnect oil lines (2), (3) and (4). 2. Remove the nuts (6) and bolts that hold the valve to the frame.3. Remove boom check and relief valve (5).Install Boom Check And Relief Valve
1. Put the valve (1) in position on the frame and install the three bolts and nuts (4) that hold it. 2. Install oil line (2). Connect oil lines (3), (5) and (6) to the boom check and relief valve.Disassemble Boom Check And Relief Valve
start by:a) remove boom check and relief valve 1. Remove plugs (1) and (2) from the valve. Remove O-ring seals from the plugs. 2. Remove spring retainer (3), spring (4) and valve (5) from the valve body.3. Remove spring (7) and valve group (11) from the valve body.4. Remove seat (8), valve (6), spring (9) and shims (10) from valve group (11). Remove O-ring seal from the seat.Assemble Boom Check And Relief Valve
1. Put shims (10), spring (9) and valve (8) in position in the valve group (11), then install the seat (7). Make sure the O-ring seal is in position on seat (7).2. Install the valve group (11) and spring (6) in the valve body. Put a new O-ring seal on plug (5). Install plug (5) in valve body.3. Install valve (4), spring (3) and spring (2) in the valve body. Put a new O-ring seal on plug (1), then install plug (1) in the valve body.end by:a) install boom check and relief valveb) check adjustment of relief valve (See ADJUSTMENT OF LINE RELIEF VALVES in TESTING AND ADJUSTING)