Fluid Leak Diagnosis
Possible Leak Points:
METHODS FOR LOCATING LEAKS
You can generally locate and repair the cause of most external leaks with the transmission in the vehicle. Use any one of the following methods for locating leaks:
1. Thoroughly clean the suspected leak area with a solvent.
2. Remove the converter shield, if required.
3. Apply an aerosol type powder such as foot powder to the suspected leak area.
4. Start the engine and run at fast idle.
5. Repair leaks and recheck as necessary.
^ Identify the type of oil (transmission fluid contains a red dye).
^ Leaking oil is generally carried toward the rear of the car by the air stream.
6. Drive the car approximately 15 miles to warm up unit to operating temperature 88°C (19O°F).
7. Inspect the car for leaks with the engine running.
8. Turn the engine OFF, check for leaks caused by drain back.
Possible Points of Oil Leaks
1. Oil may leak from the transmission pan or valve body cover for the following reasons:
^ The attaching bolts are not torqued correctly.
^ The gasket is damaged or improperly installed.
^ The oil pan or the mounting face of the valve body cover is not flat.
2. Oil may leak from the case for the following reasons:
^ Servo cover porosity or O-Ring damage.
^ The multi-lip seal on the filler tube is damaged or missing.
^ The filler pipe bracket is mislocated.
^ The electrical connector O-Ring is damaged.
^ The manual shaft seal is damaged.
^ The oil cooler connector fittings are loose or damaged.
^ The vacuum modulator O-Ring is damaged.
^ The axle oil seals are worn or damaged.
^ The park lock out cup plug is loose.
^ The line pressure pickup pipe plug is loose.
^ The bottom pan or side cover gaskets are damaged.
^ The casting is porous.
3. Oil may leak from the converter end for the following reasons:
^ The converter seal is damaged.
- The seal lip is cut (check converter hub for damage).
- The bushing has been moved forward and is damaged.
- A garter spring is missing from the seal.
^ The converter is leaking from a weld area.
^ A casting is porous in the case or the drive sprocket support.
^ The oil seal on the turbine shaft is worn or damaged.
4. Fluid may come out from the vent pipe under the following conditions:
^ Overfilled
^ If the fluid appears milky, water or coolant may be in the fluid.
^ The case is porous.
^ The fluid level indicator registers incorrectly.
^ The drain back holes are plugged.
^ The case to the modulator gasket on the channel plate is mispositioned or damaged.
^ The thermal element has been set to the incorrect height.
Engine Coolant in Transaxle
Notice: Antifreeze will deteriorate the Viton O-Ring seals and the glue used to bond the clutch material to the pressure plate. Both conditions may cause transaxle damage.
Perform the following steps if the transmission oil cooler has developed a leak, allowing engine coolant to enter the transmission:
1. Because the coolant will attack the seal material causing leakage, disassemble the transmission and replace all rubber type seals.
2. Because the facing material may become separated from the steel center portion, replace the composition-faced clutch plate assemblies.
3. Replace all nylon parts including washers.
4. Replace the torque converter.
5. Thoroughly clean and rebuild the transmission, using new gaskets and oil filter.
6. Flush the cooler lines after you have properly repaired or replaced the transmission cooler.
Cooler Flushing and Flow Test
Notice: You must flush the cooler whenever you remove a transmission for service. Cooler flushing is essential for SRTA installation, major overhaul, whenever you replace a pump or torque converter, or whenever you suspect that the fluid has been contaminated. Use J 35944 to flush the cooler.
After filling the transmission with fluid, start the engine and run for 30 seconds. This will remove any residual moisture from the oil cooler. A minimum of two quarts of fluid should flow during a 30-second period. To check the fluid flow, disconnect the return line at the transmission and observe the flow with the engine running. If the fluid flow is insufficient, check the fluid flow by disconnecting the feed line at the cooler. Observe the flow with the engine running.
^ If the flow from the cooler return line at the transmission is insufficient, check the flow rate from the feed line to the cooler. Blockage exists in the transmission or the cooler.
^ If the flow from the transmission feed line to the cooler is insufficient, the transmission is the cause of the fluid flow problem.
^ If the flow from the transmission feed line to the cooler is sufficient, but flow from the cooler return line to the transmission is insufficient, inspect the cooler pipes and fittings. Then repeat the cooler flushing procedure. If the flow is still insufficient, replace the cooler.