TM 5-3805-290-23-1
THEORY OF OPERATION - CONTINUED
0003 00
TRANSMISSION - CONTINUED
(3)
Machine is equipped with these modu-
lating valves:
(a) Modulating valve for clutch 1 (for-
ward low).
(b) Modulating valve for clutch 2 (for-
ward high).
(c) Modulating valve for clutch 3
(reverse).
(d) Modulating valve for clutch 4 (sec-
ond speed).
(e) Modulating valve for clutch 5 (third
speed).
427-B1697
(f) Modulating valve for clutch 6 (first
speed).
Neutral.
(4)
(a) When machine ECM requires a clutch to be disengaged, there is no flow of electric current to sole-
noid. Pump oil flows into valve body from pump passage. Oil then flows into passage, through orifice,
and into chamber. Since there is no signal sent to solenoid, pin cannot hold ball against orifice. Oil
flows through orifice, past ball, to tank passage. Oil in tank passage becomes return oil.
(b) Spring holds valve spool left. When valve spool is shifted left, oil in clutch passage flows to tank pas-
sage. When oil in clutch passage is vented to tank, clutch cannot be engaged. Oil in pump passage is
blocked from entering clutch passage.
427-B1699
0003 00-50
