John Deere stx38 - Manual (Page 186)

5 - 22
3/21/97
THEORY OF OPERATION POWER TRAIN
TRANSAXLE OPERATION
PEERLESS MODEL 920-017,
930-004 & 930-004A
STX30 (SN —135158)
(SN 160759— ) &
STX38 (SN —139614)
(SN 185587—210000)
Function:
The transaxle transmits power from the engine,
through the belt traction drive system, into the
transaxle gear matrix, and out the drive axles to the
rear wheels. The transaxle provides a gear selection of
five forward speeds and one reverse speed.
It also provides the means to interrupt the flow of power
when shifted into neutral.
Major Components:
• Transaxle drive sheave
• Input shaft and pinion gear
• Beveled drive gear, drive shaft with small drive
chain sprocket, drive chain, and drive gears
• Intermediate shifter/brake shaft with shifter fork,
shift collar, shift keys, large drive chain sprocket/
reverse gear, drive chain, and transfer gears
• Idler shaft and combination gear
• Differential gears and axle shafts
• Wheels and tires.
Theory of Operation:
Forward:
The transaxle input sheave is keyed to the input pinion
(J). The input pinion (J) drives the input bevel gear (I)
and forward drive gears (H). A gear is selected when
the shift lever (D) moves the shift collar (C) and shift
keys (F) to lock one of the driven gears to the shifter/
brake shaft (G). Power is transmitted by the gears on
the right-hand end of the shifter/brake shaft (G) and
counter shaft (B), back to the differential ring gear (A).
Reverse:
When reverse gear is selected, power is transmitted
from the input pinion (J) and input bevel gear (I),
through the reverse gear and drive chain (E). The
chain, drives the shifter/brake shaft (G) in the opposite
direction then the gear sets did, therefore, giving a
reverse direction to the counter shaft (B) and
differential (A).
Neutral:
In neutral the shift fork places the keys (F) in an area
where there is no power transmitted to the shifter/brake
shaft (G) and neutral is attained.
M42157
A
I
J
B
C
D
G
E
F
H
M42157
A
I
J
B
C
D
G
E
F
H