Agilent Technologies 1290 Infinity II 2D-LC User Manual page 328

12 Maintenance
Replace Valve Heads
1 Insert the valve head into the valve shaft.
OR
If the outside pin does not fit into the outside groove, you
have to turn the valve head until you feel that the two pins
snap into the grooves. Now you should feel additional
resistance from the valve drive while continuously turning
the valve head until the pin fits into the groove.
2D-LC User Guide
2 When the outer pin is locked into the groove, manually
screw the nut onto the valve head.
NOTE
Fasten the nut with the 5043-1767 Valve Removal tool.
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