Torque Converter Evaluation

The torque converter is composed of a pump impeller (which is rotated by the engine flywheel), a turbine runner and a lock-up clutch which are fixed to the transaxle input shaft by means of a one-way clutch, and a stator which is attached to the stator shaft by the one-way clutch. The pump impeller is rotated by the engine, causing fluid flow inside the converter. The fluid flow rotates the turbine runner, transmitting torque to the transaxle input shaft. During torque converter lock-up, the lock-up clutch is pushed against the front cover so that engine torque is directly transmitted to the transaxle input shaft.

The torque converter assembly serves three primary functions. First, it acts as a fluid coupling by using fluid to smoothly connect engine power to the transaxle assembly during non-torque converter lock-up conditions. Second, it has the capability of lock-up providing a direct drive from the engine to the transaxle input shaft. And third, it multiplies the torque (twisting effort) from the engine when additional performance is desired. Because the torque converter is incapable of disassembly, service parts are not available for the torque converter assembly. Any problems that exist with the torque converter can only be corrected by replacement of the assembly.

The torque converter must be replaced if any of the following conditions exist:
- External leaks in the hub weld area.
- Converter hub is scored or damaged.
- Converter pilot is damaged or fits poorly into crankshaft.
- Metal particles are found after flushing the transaxle cooler and cooler pipes/hoses.
- Pump is damaged or metal particles are found in the converter.
- Converter has an imbalance which cannot be corrected.
- Converter has been contaminated with engine coolant.
- Internal failure of stator.
- Heavy amounts of clutch material due to overheating (parts of converter exterior may appear blue).
- If metal particles or clutch material are found in transaxle fluid pan or on pan magnet when no internal parts in the unit are worn or damaged, the material came from the converter.