Shimano NEXUS SG-C7002-5 Dealer's Manual page 43

Maintenance
Oil maintenance of the internal assembly
2. Remove the oil port screw and O-ring.
Be careful that the oil port is facing up; if the oil port screw is loosened when it is not facing up, the
oil inside may leak out.
3. Attach the bleed nipple with tube to the hub shell.
Hub shell
Bleed nipple
1 - 3 N·m
Check that the O-ring is properly installed on the bleed nipple.
4. With the piston of the syringe pushed fully in, firmly connect the syringe to the tube.
Oil port screw
O-ring
Tube
Tube
Syringe
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