Maintenance Of Suction Throttle Valve - Hitachi NEXT Series Service Manual

4.16 Maintenance of Suction
Throttle Valve
4.16.1 Removing the Suction Throttle
Valve Assembly
① Remove the air intake filter. See the air intake filter
maintenance manual for details.
② Remove the filter box, filter box gasket (513) and U
cover (1) (554).
③ Remove the pipes of air cylinder operating
components and the air exhaust valve.
④ Remove the bolt that attaches the air intake duct to
the 1st-stage air end block. After that, raise the suction
throttle valve assembly using a hoist to remove it.
After removing the suction throttle valve assembly,
take necessary measures to prevent foreign matter
from entering the air intake of the 1st-stage air end,
such as covering the opening with a cloth.
① Remove the air cylinder from the STV body.
② Remove the blowoff silencer assembly from the air
cylinder.
532
534
509
522
516
569 （ ※2）
551 （ ※2）
508
506
550
540 （ ※1）
510 （ ※1）
539
505
521
519
507
535
536
525
540
515
504
F28
515
526
514
574
529
501
500
Fig. 2 Suction throttle valve structure (2)
Confidential to Customer
Blowoff
Silencer
Assembly
Fig. 1 Suction throttle valve structure (1)
522
520
503
518
518
517
520
541
542
558
559
530
511
502
37
Unloader Body
Air Intake Duct
Air Cylinder
Air Intake Filter
537
F27
F44
512
513
512
554
513