1 / 97

OBJECTIVES

OBJECTIVES. After studying Chapter 18, the reader should be able to: Disassemble and reassemble automatic transmission subassemblies. Determine if used subassemblies and their components are usable. Complete the ASE tasks related to off-vehicle transmission/transaxle repair.

kacy
Télécharger la présentation

OBJECTIVES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. OBJECTIVES After studying Chapter 18, the reader should be able to: • Disassemble and reassemble automatic transmission subassemblies. • Determine if used subassemblies and their components are usable. • Complete the ASE tasks related to off-vehicle transmission/transaxle repair.

  2. SUBASSEMBLY REPAIR • Inspection, service, and repair operations are done to each of the transmission subassemblies as part of the transmission overhaul. • These subassemblies include the case, pump, clutch assemblies, gearset, valve body, and governor. • Subassembly repair ensures that each component is serviceable and will work properly when the transmission is assembled.

  3. CASE INSPECTION • Several areas of the case should be checked or serviced after it has been cleaned. • These include the bushings, all fluid passages, the valve body worm tracks (grooves for the valve body fluid flow), all bolt threads, the clutch plate lugs, and the governor bore.

  4. FIGURE 18-1 This tool is designed to attach to the rear of an E4OD or C6 case. It guides a reamer that will cut the damaged bore to a larger diameter; an oversized bushing is then used to repair the case and a more durable bushing is installed. (Courtesy of Sonnax) CASE INSPECTION

  5. FIGURE 18-2 A flat, smooth file is being drawn (moved in the direction of the arrow) across the valve body area of a case to smooth out any dings or warpage. TECH TIP • Some technicians draw file the valve body area using a 16-in., single-cut file as standard practice. • To draw file a case, place the case with the worm tracks upward, lay the file flat, grip each end of the file, and draw the file sideways across the case.

  6. FIGURE 18-3 This worm track (arrow) has been closed off and filled with ATF to check for a suspected leak (a). The low-reverse clutch failed because of a pressure loss through a crack (circled) (b). It was found by watching ATF leak out of the crack. TECH TIP • If a low-mileage transmission has failed because of a burned clutch or band you should check for pressure loss and cross leaks.

  7. FIGURE 18-4 This case shows wear in the area where the lowreverse clutch plates contact the lugs. This case is still usable, but excessive wear might hamper proper clutch apply and release. CASE INSPECTION

  8. FIGURE 18-5 Governor bore wear is checked by placing the case on its back (a); inserting the test tool into the governor bore (b); filling the passage with ATF (c); and seeing how long it takes for the fluid to leak down to point A. (b is courtesy of Sonnax) TECH TIP • The governor bore size can be checked by placing the governor into its bore and filling the passages with ATF.

  9. FIGURE 18-6 A small cylinder hone dipped in ATF can be used to smooth out minor scores in a governor bore. It should be turned by hand. Power tools should not be used. TECH TIP • Minor scores in a governor bore can be cleaned using a small cylinder hone.

  10. FIGURE 18-7 An A4LD tends to wear the manual shift linkage bore and leak fluid. The case can be repaired by reaming the bore oversize and installing a repair sleeve. (Courtesy of Sonnax) TECH TIP • Some transmissions develop a fluid leak around the shift shaft because of a worn bore. • A repair kit has been developed that includes a reamer, reamer guide, repair sleeve, and retaining pins

  11. FIGURE 18-8 A damaged or worn accumulator bore can be repaired by installing a sleeve and a matching piston. (Courtesy of Sonnax) TECH TIP • Some accumulator bores tend to wear because of repeated accumulator piston oscillation.

  12. FIGURE 18-9 The manual valve shaft seal is driven into place using a seal driver. CASE INSPECTION

  13. PUMP SERVICE • Service of most pumps consists of the following: • Disassembly • Inspection of the pumping members, stator support shaft, front bushing, clutch support surface, and sealing ring grooves • Checking of all valves • Cleaning of all fluid passages, including the drainback hole • Replacement of the front seal • Reassembly

  14. FIGURE 18-10 The pump gears and their cavity are carefully checked for wear and the front seal is normally replaced. (Courtesy of Chrysler Corporation) PUMP SERVICE

  15. FIGURE 18-11 The rotor and slide of this vane pump are broken (a) and the pump body (b) is badly scored. This pump must be replaced. PUMP SERVICE

  16. FIGURE 18-12 Clearance checks of the pump gears include end clearance (a), gear-to-housing clearance (b), and gear-tooth clearance (c). (Courtesy of Chrysler Corporation) PUMP SERVICE

  17. FIGURE 18-13 An exploded view of a vane-type pump. Wear checks include the rotor, vanes, slide, pump body, and pump cover. PUMP SERVICE

  18. FIGURE 18-14 If replacement is needed for the pump rotor (a), vanes (b), or slide (c), they should be measured to determine the proper size. (Reprinted with permission of General Motors) PUMP SERVICE

  19. FIGURE 18-15 A new front seal is being installed using a seal driver (SST). PUMP SERVICE

  20. FIGURE 18-16 A replacement stator support shaft for a 4L60 transmission that uses a set screw to prevent rotation of the inner sleeve. (Courtesy of Sonnax) PUMP SERVICE

  21. FIGURE 18-17 Fluid flowing through the pump bushing must be allowed to flow to the pan through the drainback passage. If this passage is blocked, a drill bit of the proper size should be used to clean it out. (Reprinted with permission of General Motors) TECH TIP • Metal caged lip seals are not designed to retain pressure. • The fluid that is fed to lubricate the front bushing normally drains back into the transmission case through a drainback hole between the bushing and the seal.

  22. FIGURE 18-18 These special tools are used to align the pump gears of certain Ford transmissions while the bolts are tightened. (Courtesy of ATEC Trans-Tool and Cleaning Systems) PUMP SERVICE

  23. FIGURE 18-19 Special tool J25025-1 is being used to align the pump body and cover before tightening the bolts (a). A long screw clamp can be used for this same purpose (b). (a is reprinted with permission of General Motors) PUMP SERVICE

  24. FIGURE 18-20 The pump body and cover can be aligned correctly by placing them into the case upside down while the bolts are tightened. TECH TIP • An alternate aligning method is to place the pump upside down in an empty transmission case before tightening the bolts.

  25. CLUTCH ASSEMBLY SERVICE • The service procedure for most clutch assemblies is as follows: • Remove the clutch plates and disassemble the return spring(s) and piston. • Thoroughly clean the parts. • Inspect the drum, piston, and check ball as well as the bushing and seal ring area. • Install new seals on the piston. • Install the piston and return spring(s). • Install the clutch plates. • Check the clutch clearance.

  26. FIGURE 18-21 An exploded view of a clutch assembly; note the clutch stack with four frictions and the strong piston spring. (Courtesy of Chrysler Corporation) CLUTCH ASSEMBLY SERVICE

  27. FIGURE 18-22 The large snap ring can usually be removed using a screwdriver or seal pick (a) and then the pressure plate and clutch plates can be removed (b). CLUTCH ASSEMBLY SERVICE

  28. FIGURE 18-23 This variety of clutch spring compressors includes completely portable ones (a, b, and c), a bench-mounted style (d), and a large, foot-operated style (e). (a, left, is courtesy of Chrysler Corporation; a, right, is courtesy of Kent-Moore; b is courtesy of OTC; d and e are courtesy of KD Tools) CLUTCH ASSEMBLY SERVICE

  29. FIGURE 18-23 (CONTINUED) This variety of clutch spring compressors includes completely portable ones (a, b, and c), a bench-mounted style (d), and a large, foot-operated style (e). (a, left, is courtesy of Chrysler Corporation; a, right, is courtesy of Kent-Moore; b is courtesy of OTC; d and e are courtesy of KD Tools) CLUTCH ASSEMBLY SERVICE

  30. FIGURE 18-24 Some clutch assemblies do not use a spring in each of the pockets. Note how they are arranged in this clutch. (Courtesy of Chrysler Corporation) TECH TIP • While the return springs are being removed, be sure to note the number and location of the springs if all of the pockets are not filled with springs.

  31. FIGURE 18-25 A piston can be removed by slamming the clutch downward on a block of wood (a) or applying air pressure in the apply port (b). CLUTCH ASSEMBLY SERVICE

  32. FIGURE 18-26 This piston is made from stamped steel parts that can separate. It is tested by inserting a screwdriver and trying to pry the grooves open with a light pressure. TECH TIP

  33. FIGURE 18-27 The check ball should be free to move inside its cage. It should also seal low-pressure air flow in one direction (left) and leak in the other (right). CLUTCH ASSEMBLY SERVICE

  34. FIGURE 18-28 This bushing appears usable and the two sealing ring areas (arrows) show normal operation. CLUTCH ASSEMBLY SERVICE

  35. FIGURE 18-29 This rear clutch stack has a selective snap ring, top pressure plate, four friction disks, three steel plates, bottom pressure plate, and wave spring to retain the Belleville piston spring. (Courtesy of Chrysler Corporation) CLUTCH ASSEMBLY SERVICE

  36. FIGURE 18-30 With the clutch assembled and lying flat, you should feel a definite drag if you try to rotate the plates (left). The plates should rotate easily with the clutch vertical (right). TECH TIP • Always check to be sure the plates turn freely with the clutch released.

  37. FIGURE 18-31 The clutch pack clearance specification for this clutch is 0.025 to 0.045 in.(0.64 to 1.14 mm). A 0.025-in.feeler gauge should enter as shown, but a 0.045-in. feeler gauge should be very tight or not fit in at all. (Courtesy of Chrysler Corporation) CLUTCH ASSEMBLY SERVICE

  38. FIGURE 18-32 A dial indicator can be set up with the stylus on the piston to measure piston stroke (a). Applying air to the proper passage should cause the piston to stroke so the travel can be measured (b). TECH TIP • Clearance can also be measured using a dial indicator.

  39. FIGURE 18-33 This reaction clutch is deep in the case, and the clearance is measured by lifting a clutch plate while watching the dial indicator (a). Clutch clearance is adjusted by selecting the proper reaction/pressure plate (b). (Courtesy of Chrysler Corporation) TECH TIP

  40. FIGURE 18-34 This clutch pack is assembled and the height is measured. The height should be within the specified dimensions. TECH TIP

  41. FIGURE 18-35 Clutch clearance can be reduced by adding an extra unlined plate (a and b) or lined plate (c). If two lined plates are next to each other as in c, clearance can be increased by shaving the lining off one or both adjacent sides of the two lined plates. TECH TIP • If the selective parts do not correct the clearance or are not available, clutch clearance can be reduced by using extra-thick steel plates or adding an extra unlined steel or lined friction plate.

  42. FIGURE 18-36 Air pressure is applied to the shaft clutch apply port (a) to apply and air test the clutch piston. The amount of piston stroke and clutch pack clearance are measured using a dial indicator. The special service tool (SST) allows the dial indicator to reach the piston. (b courtesy of Toyota Motor Sales USA, Inc.) TECH TIP • Most technicians air check a clutch as soon as it is assembled. • When air pressure is applied to the clutch, the piston should stroke, squeeze the clutch together, and not leak

  43. CLUTCH ASSEMBLY SERVICE • One-Way Clutch Service • One-way clutches are visually inspected during transmission disassembly and reassembly (see Section 16.6). • The commonly encountered problems are: severe wear from poor lubrication or metal fragments from a failed part; wear or scoring of the race(s), rollers, or sprags; and a sprag(s) that flips over. • One-way clutches should always be lubricated using assembly grease, petroleum jelly, or ATF during assembly.

  44. FIGURE 18-37 This gearset should have 0.005 to 0.048 in. (0.12 to 1.22 mm) of end play. A 0.005-in. feeler gauge should enter as shown, but a 0.049-in.gauge should not. (Courtesy of Chrysler Corporation) GEARSET SERVICE • Servicing gearsets is primarily a visual inspection of the various gears and a side play and rotation check of the planet gears. • In some cases there is also an end-play check of the assembled gear train to ensure the thrust washers are not worn excessively.

  45. FIGURE 18-38 This kit includes the parts needed to rebuild a 4L60 planetary assembly. (Courtesy of Sonnax) GEARSET SERVICE

  46. FIGURE 18-39 Planetary gear train damage shows up as wear (a–d) or cracks and breakage (e). GEARSET SERVICE

  47. FIGURE 18-39 (CONTINUED) Planetary gear train damage shows up as wear (a–d) or cracks and breakage (e). GEARSET SERVICE

  48. FIGURE 18-40 These three gear train components show severe wear and scoring in the thrust surfaces. GEARSET SERVICE

  49. FIGURE 18-41 These sun gear drive shells show stripped splines (a) and broken, dislodged splines (b). GEARSET SERVICE

More Related