A/T - Warm Surge At Steady Speeds

87chrysler10

Models


1985-1987 LA (Colt) & NF45Z (Colt Vista) Vehicles Equipped With a KM 171 or 172 Automatic Transaxle


Subject


Warm Surge at Steady Speeds


Index


DRIVEABILITY


Date

March 23, 1987

No..


18-08-87 (C2-18)

P-990
SYMPTOM/CONDITION

Engine may surge at full operating temperature with the vehicle at steady cruise/light load condition.

DIAGNOSIS

If a surge from 100 to 200 rpm can be felt when the engine speed is between 1800 and 2600 rpm, disconnect the automatic transmission control unit. If the surge is gone, proceed with the following repair procedure.

PARTS REQUIRED

Transmission Modification Package PN MD728159

Consists of:

1 Damper Clutch Control Valve PN MD727246
1 Damper Clutch Control Sleeve PN MD723456
1 Lower Valve Body PN MD727244
1 Lower Valve Spring PN MD725203
1 Solenoid Valve PN MD727245
1 Gasket, Oil Pan PN MD707183
2 O-Ring PN MD707603
1 O-Ring PN MD707752

REPAIR PROCEDURE

This procedure involves replacing the transmission lower valve body damper clutch control valve, sleeve, and spring, and the lock-up solenoid valve. This will correct a lock-up transmission induced engine surge.

FIGURE 1:

1. Remove the transmission oil pan and oil filter per service manual procedure.

2. Remove the 13 mounting bolts securing the lower valve body, and remove the lower valve body from the valve body assembly, making sure the lower separator plate comes with the lower valve body (Figure 1).

CAUTION: THREE STEEL BALLS AND A SPRING WILL COME OUT WHEN THE LOWER VALVE BODY IS SEPARATED FROM THE UPPER VALVE BODY.

FIGURE 2:

3. Remove the end cover from the lower valve body by removing the three attaching bolts.

4. Clean and lubricate the new damper clutch control valve assembly (PN MD727246, MD723456, and MD725203) with Dextron II, and install them in the new lower valve body, PN MD727244. Transfer the remaining parts from the old lower valve body to the new lower valve body (Figure 2).

FIGURE 3:

5. Install the end cover and tighten the three attaching bolts to 52 inch pounds.

6. Assemble the lower valve body and lower separator plate, making sure the stopper plate is installed (Figure 3).

FIGURE 4:

7. Using petroleum jelly to hold them in place during assembly, install the three steel balls and spring removed in Step 2 into the lower side of the upper valve body (Figure 4).

FIGURE 5:

8. Install the lower valve body and separator plate assembly to the upper valve body (Figure 5). Torque the 13 bolts to 52 inch pounds.
9. Loosen the solenoid mounting bolts and remove the solenoid valve.

10. Apply Dextron II to the O-ring and install the new solenoid valve, PN MD727245. Torque the mounting bolts to 52 inch pounds.

11. Install the filter and oil pan per service manual procedures.


POLICY: Reimbursable within the provisions of the warranty

TIME ALLOWANCE:
Labor Operation No. 21-95-01-90 . . . . . . . . . . . .1.4 Hrs.

FAILURE CODE: RO - Driveability