John Deere stx38 - Manual (Page 225)

3/20/97
5 - 61
POWER TRAIN REPAIR
Inspect Idler Combination Gear Assembly:
1. Visually check overall condition of assembly,
including shaft and bushings, gears for wear,
pitting, broken teeth, etc.
2. Use a feeler gauge to measure “go/no go” air gap
(A) between end surface of combination gear and
side surface of case half:
• “GO” air gap should be 0.33—0.63 mm (0.013 —
0.025 in.)
• “NO GO” air gap is anything greater.
3. If measurement results in a “NO GO” reading, worn
and damages components need to be replaced.
Disassemble Idler Combination Gear Assembly:
1. Lift idler combination gear assembly (A) from lower
case half.
2. Clean components individually once disassembled.
STX38 (SN 210001—301382) and STX46 Transaxle
3. Separate and inspect assembly components:
• washers (B and D) should be 0.632 x 1.00 x 0.026
in., not scored or discolored (burnt)
• spacer (C) should be 0.630 x 1.00 x 0.169 in., not
scored or discolored (burnt)
• narrow combination gear (E) should have 35 good
teeth and wide combination gear (F) should have
12 good teeth, not scored or discolored (burnt)
• idler shaft (G) should be smooth and not scored,
pitted, or discolored (burnt)
• shim washer(s) (H) are found in Shim Kit.
• inside bearing (I) and outside (K), which are press
fit, should not be scored nor discolored (burnt);
• gear bore (J) should not be scored or discolored
(burnt). Replacement gear has needle bearings
(with special grease) and a new shaft is also
recommended whenever a new gear is ordered.
STX38 (SN 301383— ) Transaxle
4. Separate and inspect assembly components:
• washers (B) should be 0.632 x 1.00 x 0.026 in., not
scored or discolored (burnt)
• narrow combination gear (C) should have 30 good
teeth and wide combination gear (D) should have
12 good teeth, not scored or discolored (burnt)
• idler shaft (G) should be smooth and not scored,
pitted, or discolored (burnt)
• shim washer (F) is found in Shim Kit
M42523
A
A
M42324
M42325
B C D
E
F
G H
M42326
I
K
J
M88996
B
C
D
E
F