GMC 4000 Series Service Manual page 505

Sec. 9B
G M C S E R V I C E M A N U A L
Page 494
POWER STEERING
9 ::v :v :;:v :v * v X $
VIEW A -P U M P O PERATIO N -LO W SPEED
LEGEND
12
| !!!| DISCHARGE OIL
SUPERCHARGE OIL
HIGH PRESSURE OIL
RESERVOIR AND RETURN
RING-ROTOR LEAKAGE OIL
VIEW B-P U M P O PERATIO N -H IGH SPEED
T-1166
Figure 6 — V a n e Type H ydraulic Pum p O peration