Leakage Inspection

Check the Vehicle Speed Sensor (VSS) and speedometer cable connection at the transaxle. Replace the rubber seal if necessary.

Leakage at the transaxle pan to case gasket often can be stopped by tightening the retaining bolts to specification. If necessary, replace the transaxle pan-to-case gasket.

Check the chain cover gasket.

Check the wiring connector to chain cover. Replace wiring connector assembly, if necessary.

Check the fluid filler tube connection at the case. If leakage is found here, install a new grommet.

CAUTION: Do not try to stop the fluid leak by increasing the torque beyond specification. This may cause damage to the case threads.

Check fluid lines and fittings at the transaxle and the cooler in the radiator tank, and the auxiliary cooler for looseness, wear or damage. If leakage cannot be stopped by tightening a fluid tube nut, replace the damaged parts. When fluid is found leaking between the case and cooler line fitting, check for missing or damaged O-ring, then tighten the fitting to maximum specification.

CAUTION: Do not try to stop the fluid leak by increasing the torque beyond specification. This may cause damage to the case threads.

If the leak continues, replace cooler line fitting and tighten to specification. The same procedure should be followed for fluid leaks between the radiator cooler and the cooler line fittings.

Check the engine coolant in the radiator. If transmission fluid is present in the coolant, the transmission fluid cooler in the radiator is probably leaking.

The transmission fluid cooler can be further checked for leaks by disconnecting the lines from the cooler fittings and applying 345 kPa (50 psi) air pressure to the fittings. Remove the coolant recovery cap to relieve the pressure buildup at the exterior of the transaxle fluid cooler tank. If the transmission fluid cooler is leaking and/or will not hold pressure, the transmission fluid cooler must be replaced.

Check for fluid leaking from the differential seals. Leakage may result from damaged seals, missing garter springs or a worn halfshaft/linkshaft. Replace the seal and/or halfshaft as necessary. If leakage is found at the manual lever replace the seal.

Check the steering gear system. The power steering gear system is positioned over the rear of the transaxle and is filled with transmission fluid. Leaks from the steering gear may pool on the transaxle before dripping onto the ground, thus giving the appearance of a transmission fluid leak.

Inspect both components carefully before disassembling either. If the power steering system is found to be leaking. After an engine oil filter change, some residual oil may blow back on the transaxle giving the appearance of transmission fluid leakage. The area should be cleaned and checked after running the engine.

External Sealing








The AX4S transaxle has the following parts to prevent external fluid leakages.





Fluid Leakage in Torque Converter Area
In diagnosing and correcting fluid leaks in the torque converter area, use the following procedures to locate the exact source of the leakage. Leakage at the front of transaxle, as evidenced by fluid around the torque converter housing, may have several sources. By careful observation, it is possible in many instances to pinpoint the source of the leak before removing the transaxle from the vehicle. The paths which the fluid can take to reach the bottom of the torque converter housing are as follows (numbers on illustration relate to items below):

1. Fluid leaking by the converter impeller hub seal lip will tend to move along the drive hub and onto the back of the torque converter. Except in the case of a total seal failure, fluid leakage by the lip of the converter hub seal will wet the back of the torque converter and be deposited on the torque converter housing only, near the center of the case.
2. Fluid leakage by the outside diameter of the converter impeller hub seal and case will follow the same path which the leaks by the inside diameter of the seal will follow.
3. Fluid leakage from the converter cover weld or the converter-to-flywheel stud weld will appear at outside diameter of torque converter on back face of flywheel and in the converter housing only near the flywheel. If a converter-to-flywheel stud or converter cover weld leak is suspected, remove converter and pressure check.
4. Fluid leakage from the bolts inside the converter housing will flow down the back of the torque converter housing. Leakage may be from loose or missing bolts, torn or damaged chain cover gasket.
5. Engine oil leaks are sometimes improperly diagnosed as transaxle converter hub seal leaks. The following areas of possible leakage should also be checked to determine if engine oil leakage is causing the concern.
a. Leakage at the valve cover may allow oil to flow over the converter housing or seep down between the converter housing and cylinder block causing oil to be present in or at the bottom of the converter housing.
b. Oil plug leaks will allow oil to flow down the rear face of the cylinder block to the converter housing.
c. Leakage at the crankshaft seal will work back to the flywheel and then into the converter housing.

Leak Check Test
The following procedures should be used to determine the cause of the leakage before service is made.
1. Remove the fluid level indicator and note the color of the fluid. Original factory fill fluid is dyed red to aid in determining if leakage is from the engine or transaxle. Unless a considerable amount of makeup fluid has been added or the fluid has been changed, the red color should assist in pinpointing the leak.
2. Remove the converter housing. Clean off any fluid from the top and bottom of the converter housing, front of the case and rear face of the engine and oil pan. Clean the torque converter area by washing with a suitable nonflammable solvent and blow dry with compressed air.
3. Wash out converter housing and the front of the flywheel. The converter housing may be washed out using cleaning solvent and a squirt-type oil can. Blow all washed areas dry with compressed air.
4. Start and run the engine until the transaxle reaches its normal operating temperature. Observe the back of the block and top of the converter housing for evidence of fluid leakage. Raise the vehicle on a hoist. Run the engine at fast idle, then at engine idle, occasionally shifting to the DRIVE and REVERSE ranges to increase pressure within the transaxle.
Observe the front of the flywheel, back of the block (in as far as possible) and inside the converter housing and front of the case. Run the engine until fluid leakage is evident and the source of leakage can be determined.

Leak Check Test with Black Light
Oil-soluble aniline or fluorescent dyes pre-mixed at the rate of 2.5 ml. (1/2 teaspoon) of dye powder to 0.23 liter (1/2 pint) of transmission fluid have proven helpful in locating the source of fluid leakage. Such dyes may be used to determine whether an engine oil or transmission fluid leak is present, or if the fluid in the transmission fluid cooler leaks into the engine coolant system. A black light must be used with the fluorescent dye solution.