Repairs (cont'd)
Ball Seat Refinishing
Refer to Figures B2, B3, and B4 for the proper drill size
to refinish the conical seat and finish ream size.
These operations must be performed with the pump
or valve block properly held and using a drill press.
Only a very small amount of material should be removed.
3.175 mm (.125") Ø REAM
4.76 mm (.187") Ø BALL SEAT
(P.O. VALVE)
7.14 mm (.281") Ø DRILL
11.51 mm (.453") Ø DRILL
6.35 mm (.250") Ø BALL SEAT
(LO-P RELIEF VALVE)
4.76 mm (.187") Ø REAM
Figure B2
Figure B3
Greenlee Tools, Inc.
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7
COVERPLATE
8.43 mm ("Q" 0.332") Ø DRILL
4.76 mm (0.187") Ø BALL SEAT
(INTAKE CHECK)
3.45 mm (#29 0.136") Ø REAM
4.76 mm (0.187") Ø REAM
7.14 mm (0.281") Ø BALL SEAT
(DISCHARGE CHECK)
9.35 mm ("U" 0.368") Ø DRILL
9.35 mm ("U" 0.368") Ø DRILL
7.14 mm (0.281") Ø BALL SEAT
(BYPASS CHECK)
4.76 mm (0.187") Ø REAM
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5
975 Hydraulic Power Pump
7.94 mm (0.312") Ø BALL SEAT
(LINE CHECK VALVE)
21
4455 Boeing Dr. • Rockford, IL 61109-2988 USA • 815-397-7070
7.14 mm (0.281") Ø REAM
9.53 mm (0.375") Ø DRILL
Figure B4
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