Hitachi CHROMASTER 5160 Instruction Manual page 960

(4) Detach the injection valve seal from the unit.
Injection valve seal
Injection valve stator
Fig. 5-16 Removal of Injection Valve
(5) In the reverse order of removal, attach a new injection valve
seal, the stator ring, and the injection valve stator. Then
tighten the stator setscrews. Secure these setscrews in
turn and by equal increments.
(6) In the reverse order of removal, connect the tubes and
pipes to the injection valve. (Refer to 5.2)
(7) After replacement of the injection valve seal, check that
there are no liquid leaks.
NOTES: 1. While the inside of the valve is dry, avoid moving
the valve unless otherwise necessary. Otherwise,
the plunger seal will sear out abnormally.
2. If the valve is not filled with liquid, it lacks
lubricity. Therefore, the valve may not move
normally.
Unit
Stator setscrew
5 - 17
Stator ring