Dismantling and assembling transmission - RA2703722C640X(27-640)
Operation number of the operation texts and work units or standard texts and flat rates:
27-4010
Assembling
Before installing, immerse new brake bands and lining discs of multiple-disc brake in ATF for approx. 1 hour.
- 55 Place housing (1) into assembly device and secure in place with the bolt (arrow).
- 56 Insert plastic guide ring (88a) for plunger B2, then insert lip sealing ring (88) using the shop-made drift. The sealing lip (arrow) must point in the direction of the brake band plunger cover.
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NOTE: The impact drift must be manufactured in accordance with the specified dimensions. - 57 Place O-ring (91) in groove.
- 58 Insert radial sealing ring (92).
- 59 Screw in screw plug (90) with new aluminum sealing ring and tighten to 10 Nm.
- 60 Place O-ring (arrow) in groove.
- 61 Coat grooves in support flange K2 (79) with grease. Insert Teflon rings (115) and push into the groove so that the diagonal cut (arrow) remains closed.
- 62 Insert support flange (79) following the pattern of holes for the retaining bores; use two bolts, approx. 80 mm long, for centering.
- 63 Screw in combined bolts and washers (114) and tighten to 11 Nm.
- 64 Check thrust element B2 for twisting. With the thrust element removed, the bore and tab (arrows) must align. With the thrust element installed, one spring winding of the thrust element must be visible through the bore for the lower cover oil pipe.
- 65 Insert thrust element B2 (29) with the tab (arrow) upwards.NOTE: Use of pressure element B2 (29) with increased spring force.
Vehicles with M 117/119 as of transmission no. 3 305 965
Other vehicles as of transmission no. 3 307 060
- 66 Insert support ring (113) in such a way that the lug for the anti-rotation element (arrow) is located in the housing.NOTE: As of 08/94, an axial bearing is installed instead of the support ring (113).
- 67 Re-check seating of Teflon rings on support flange (79).
- 68 Compress brake band B2 (27) at the support lugs as far as possible and insert in housing. To facilitate assembly, the brake band may be held together with the aid of the locking device (23).NOTE: As of 10/89, use of brake band B2 (27) with Raybestos coating for improved shifting quality.
- 69 Attach clutch K2 (100) onto gear set.
- 70 Insert gear set in transmission housing whilst rotating drive shaft (87).
- 71 Position transmission vertically with drive shaft (87) uppermost.
- 72 Check installed position of gear set. The gear set is correctly installed when the top edge of the connecting member (arrow) is lower than the bearing surface (138) of the outer multiple-disc LB3.
- 73 Assemble front cover with primary pump (27-630) .
- 74 Insert damping spring (134).
NOTE: As of transmission no. 3 716 425 an additional plastic washer is fitted.
- 75 Assemble discs for multiple-disc brake LB3 in the sequence illustrated in the figure and insert individually.NOTE: As of transmission no. 3 991 611, use of disk spring (85) with increased stroke.
- 76 Measure clearance "L" of multiple-disc brake LB3 and compensate.
Measuring distance "a"
Place parallel-edged block (029) on the machined surface and measure depth to outside edge of spring seat (85) using a depth gauge.
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Determining distance "b"
Place parallel-edged block (029) on plunger of multiple-disc brake (arrows) and measure depth to gasket (11) using a depth gauge.
The clearance "L" is the difference between the two measurements.
Adjust clearance "L" to its specified value of 1.5 - 2.0 mm. Variations can be compensated by means of the outer multiple-discs available in different thicknesses (133a, illustration item 75).
- 77 Coat groove in driveshaft (87) with grease. Insert lubricating pressure ring (99) and push into groove so that the gap remains closed.
- 78 Engage assembly lock (arrow) on brake band B1 (30).
- 79 Insert clutch K1 (83) whilst rotating so that the splines engage.
- 80 Insert brake band B1 (30) so that the pin of the assembly lock (arrow, figure to item 78) points towards thrust element B1.
- 81 Replace O-rings. Then insert thrust element B1 (31) with pressure pin and screw in screw plug (33) or overload protection switch (33b) and tighten to 70 Nm.
- 82 Insert brake band guide (34) ensuring that the locating pins engage in the bores in the housing and press it in until it locks in position detectably.
- 83 Measure axial play "B" for clutch K1 and correct.
Axial play "B": 0.6-1.0 mm.
Position seal (19) on front cover (10).
Place parallel-edged block (029) on flange (arrow).
Measure from parallel-edged block to gasket (11) using depth gauge (distance "b").
Place parallel-edged block (029) on machined surface of transmission housing. Measure from parallel-edged block to contact surface in clutch K1 (83) using depth gauge (distance "a").
Hold shim (95), thrust washer (96) and axial bearing (97) together and measure distance "c" using caliper gauge.
Distances "b" and "c" subtracted from distance "a" equal the axial play "B" of clutch K1. The axial play can be adjusted by inserting appropriate shims
(95, thickness 0.1, 0.2, 0.5 mm).
- 84 Insert measured shims, friction ring and axial bearing one by one into clutch K1 (see figure item 83).
- 85 Insert Teflon rings (9) with grease. Ensure that the gap in rings (arrows) remains closed. If necessary, remove rings again and shape to a smaller diameter.
- 86 Insert front cover (10) with gasket, tighten bolts (18) to 13 Nm.NOTE: The gasket may be used several times but must never be coated with sealing compound. In contrast, the combined bolts and washers (18) must be lightly coated with non-hardening sealing compound.
- 87 Rotate assembly device until output shaft (86) points upwards. Push snap ring (116) along output shaft as far as its groove
- 88 Attach helical gear (78).
- 89 Insert axial retainer (43) in transmission housing.
- 90 Insert O-ring (48).
- 91 Insert centrifugal governor (50).
- 92 Swivel axial retainer (43) towards centrifugal governor (50) so that it engages in the groove in the governor shaft (arrow).
- 93 Insert cover (46) and attach circlip (47) with the aid of a screwdriver. Then pull cover outwards so that it contacts the circlip around its entire circumference.
- 94 Insert intermediate plate (21) and O-ring (22).
- 95 Attach secondary pump (20) and tighten hexagon socket bolts (45) to 8 Nm.
- 96 Check seating of axial bracket again, screw on nut (44) and tighten to 6 Nm.
- 97 Insert oil pipe (84) and tighten hexagon socket bolt (84a) to 8 Nm.NOTE: Oil pipe (84) not used any more as of transmission no. 3 234 346.
- 98 Insert detent plate (82) with spring linkage and push in shaft (76).
- 99 Screw in hexagon socket bolt (82a) and tighten to 8 Nm.
- 100 Push roller (81) onto spring linkage (82).
- 101 Attach plastic guide (80) and push into locating bores.
- 102 Place shims (77) onto helical gear.
- 103 Push on parking lock pawl (74), insert expanding spring (75) and hook onto parking lock pawl (74).
- 104 Mount parking lock gear (73) with rotor or helical gear.
- 105 Measure axial play (C) of output shaft (clutch K2) and correct.
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Attach measuring sleeve (028) and tighten collared nut (62) to 100 Nm. Engage the parking lock pawl (arrow) to counter the nut. Attach seal (72).
Position parallel-edged block (029). Measure depth from measuring sleeve (028) to block using depth gauge. Add 15 mm to the measured distance to obtain distance "b".
NOTE: The 15 mm is the height of the parallel-edged block (20 mm) minus the edge of the measuring sleeve (5 mm). Assemble rear cover (27-440) .Place parallel-edged block (029) on the sealing surface of rear cover.
Measure from parallel-edged block (029) to the inside ring of the ball bearing using a depth gauge. Subtract 20 mm from the measured distance to obtain distance "a".
Distance "a" minus distance "b" equals the axial play "C".
Correct the axial play "C" to 0.4+01 mm by adding or removing shims (77) below the parking lock gear (73) (see figure to item 102).
- 106 Push seal (arrow) onto oil pipe (102) for (mechanical) speedometer lubrication and insert oil pipe.
- 107 Mount rear cover (70), coat hexagon bolts (71) with non-hardening sealing compound and tighten to 13 Nm (8.8) or 28 Nm (10.9).NOTE: The gasket may be used several times but must never be coated with sealing compound.
- 108 Insert washer (65).
- 109 Insert O-ring (63) into propeller flange (64).
- 110 Attach propeller flange (64), tighten double-hexagon collared nuts (62) to 120 Nm and lock in place with a suitable drift.
- 111 Screw in kickdown solenoid valve (61) and tighten to 20 Nm.
- 112 Insert modulating pressure regulator valve (59) and pressure pin (59a).
- 113 Mount vacuum unit (60) with retaining plate (57) and tighten hexagon socket bolts (58) to 8 Nm.
- 114 Mount starter lock-out switch (53), screw in hexagon bolts (55) but do not tighten.
- 115 Insert lip sealing ring (39) at brake band plunger B1 (37) so that the sealing lip points towards the outside.
- 116 Mount assembly device (026) and bolt on transmission housing.
- 117 Insert brake band plunger B1 with one pressure spring and measuring device (031).
- 118 Screw in spindle of assembly device (026) ensuring that pressure pin of brake band plunger B1 is inserted in brake band and that lip seal is not damaged.NOTE: To adjust the clearance, it is sufficient for just one pressure spring to be installed.
- 119 Insert circlip (41), release assembly device (026) and remove.
NOTE: In order to be able to remove and install the circlip (41) without slackening the screw plug or transmission overload protection switch, a chamfer (arrow) must be cut on 1st version measuring devices.
- 120 Measure clearance "L" at brake band B1 and adjust.NOTE: The thread on the measuring device (031) has 1 mm pitch, i.e. one revolution corresponds to 1 mm travel.
Screw in bolt on measuring device (031) by hand until resistance is detectable.
Using a torque wrench, screw in the bolt further, counting the revolutions, and tighten bolt to 1 Nm.
The idle travel at the brake band must be 1.8 - 2.0 mm, i.e. a torque of 1 Nm must be achieved after 1.8 - 2.0 revolutions.
The clearance can be adjusted by inserting or removing shims (136) in the pressure pin (38).
- 121 Reattach assembly device and bolt in place. Install brake band plunger cover (40) and second compression spring in place of measuring device, then remove assembly device.
Brake band plunger B1 2nd version with automatic adjuster as of transmission no. 3 746 852
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Illustration 1