DRESSTA TD-25M EXTRA, Service Manual, Page: 102 / 595

SECTION 7B
HYDRAULIC TORQUE CONVERTER
Page 16
TD-25M EXTRA DRESSTA
TORQUE CONVERTER
8. INSPECTION AND REPAIR
1. Wash all components thoroughly in a suitable solvent after the torque converter has been
disassembled. Dry thoroughly with compressed air or a clean cloth. Clean thoroughly all
sealing surfaces that were coated with LOCTITE for assembly purposes. Use caution so the
metal surface remains undamaged. Check all the oil passages for lack of passage obstructions
with compressed air.
IMPORTANT: Do not spin dry bearings with compressed air.
2. Inspect all bearings condition. Replace all bearings that do not rotate freely or show excessive
clearance.
3. It is recommended that new O-rings and oil seals be installed whenever the torque converter is
disassembled for service. Replace definitely teflon seal ring (3) at the converter input and cast
iron seal ring (15) at the converter output when excessive oil leakage occurs during the test.
4. Inspect all splined connections for excessive clearance caused by wear surfaces, surface
dents, burrs or other damages and replace if necessary. Especially, inspect both splined
connections between output shaft (14) and turbine assy (29), and between shaft (14) and
output flange (23).
5. Replace all torque converter gears and flywheel gear that tooth are worn excessively or
damage. Mating gear surfaces may show increased smoothness but any gear spalling is not
allowable.
6. Check thoroughly all bearings shaft journals and bores where bearings are seated to ensure
that there are no worn out spots due to rotation of inner bearing race on its shaft or bearing
outer race in its bore. If the check reveals that either the bearing rotates on its shaft journals or
it rotates in its bore it is seated in, both the bearing and its mating part must be replaced.
Especially, inspect mating surface between output shaft (14) and bearing (18).
7. Check turbine assy (29) riveted joints. If any rivet loose exists the entire turbine assy must be
replaced.
8. Inspect the blades of impeller (12), stator (26) and turbine assy (29) for mechanical damage. If
the blades are excessively worn or damaged, the entire assembly must be replaced.
9. Inspect thoroughly drive gear (5) inner bore that mates with seal ring (3). Drive gear (5) inner
bore and seal ring (3) contact surface shall not be grooved. If drive gear (5) inner bore is
grooved by the seal ring (3) the gear (5) must be replaced
10. Inspect ground sleeve hub (2) bore wear interacting with cast iron seal ring (15). The hub must
be replaced if it is grooved by the seal ring.
11. If any contact signs are visible on the hub surface with both drive gear (5) bore surface and
shaft (14), the hub must be replaced.
12. Output flange (23) shall not be grooved by seal ring (21) while contact surface smoothing and
darkening are admissible.
13. Replace the converter housing (1) if cracks, thread stripping or bearing bores damages occurs.