TM 9-2320-387-24-2
Table 14-1. Mechanical lYoubleshooting (Cont’d).
MALFUNCTION
TEST OR INSPECTION
I
17. NO l-2 UPSHIFT OR DELAYED UPSHIFT
Step 1.
Ifoil pressure in @
(overdrive) at 1,000 rpm is normal, proceed to step 2. Ifoil pressure
is high, proceed to step 3.
Step 2.
Check results of control valve and governor line pressure test (para- 2-41).
Step 3.
If oil pressure in N (neutral) at 1,000 rpm was normal or high, proceed to step 4.
Step 4.
Check control valve spacer plate for obstructions. Clean or replace spacer plate (chapter 28).
END OF TESTING!
18. l-2 SHIFT SOFT OR SUPS
step 1.
step 2.
step 3.
step 4.
step 5.
Step 6.
step 7.
Step 8.
step 9.
step 10.
step 11.
step 12.
step 13.
step 14.
Check transmission oil pressure response to varying throttle openings. Pressure should
respond rapidly to quick changes in throttle opening. If oil pressure response is poor,
proceed to step 2. If oil pressure response is normal, proceed to step 3.
If oil pressure in (D3 (overdrive) at 1,000 rpm is low, proceed to step 3. If oil pressure is
normal, proceed to step 9.
Check oil pump for obstructed oil passages or damage. Repair oil pump (para. 28-18).
Check forward clutch seals for damage. Replace damaged seals (para. 28-111.
Check center support oil seal rings for damage. Replace damaged rings (para. 28-9).
Check rear servo piston and oil seal rings for damage. Repair rear servo (para. 28-16) if
damaged.
Check front accumulator piston and oil seal rings for damage. Replace control valve
(chapter 281 if accumulator piston components are damaged.
Check transmission case for internal damage or porosity. Replace _transmission
(para. 19-3)
ifcase is damaged or porous.
Inspect control valve for nicks on machined surfaces or voids in casting. Check l-2
accumulator valve train for stuck valves or incorrect assembly. Check front accumulator
piston and oil seal rings for damage. Replace control valve (chapter 281 if any damage is
found.
Check rear servo and rear accumulator pistons and oil seal rings for damage. Repair rear
servo (para. 28-16) if damaged.
Check center support bolt for looseness. Tighten to 20-25 lb-R (27-34 N-m).
WARNING
Compressed air used for cleaning purposes will not exceed 30 psi
(207 kPa). Use only with effective chip guarding and personnel
protective equipment (goggles, shield, gloves, etc.).
Air-check intermediate clutch piston for proper operation. If operation is normal, proceed
to step 13. If piston exhibits excessive leakage, proceed to step 14.
Check intermediate clutch piston, plates, and release springs for damage or incorrect
assembly. Repair intermediate clutch piston (para. 28-14) if damaged.
Check center support for missing orifice plug. Replace transmission (para. 19-3) if plug is
missing.
END OF TESTING!
14-9
