Removing and Installing Front Cover and Primary Pump

Removing and Installing Front Transmission Cover and Primary Pump

Preceding work:
Removing and installing transmission with torque converter. Remove and Installing Transmission With Torque Converter






Front transmission cover (10)
Remove and install by unscrewing, screwing in bolts (18), 13 Nm, check gasket (19) (steps 1 and 2).

Teflon rings (9)
Take off, insert, stick in place with grease, joint of rings must remain together (step 3)

Snap ring (15)
Remove, insert by tensioning spring plate (13) with assembly device 201 589 12 43 00 (step 4).

Spring plate (13) and return springs (14)
Take off, fit on (step 5).

Piston LB3 (12)
Withdraw, check lip seals (16, 17), renew if necessary. Pay attention to installation instruction (step 6), insertion sleeve 126 589 02 14 00.

Primary pump (1 - 4)
Remove, install by slackening bolts (8), 20 Nm. Withdraw pump wheels (3 and 4), insert, check. Chamfer of primary pump wheel (4) must be facing bearing bush in primary pump housing cover (steps 7 - 9).

Radial seal (6) and O-ring (7)
Check, renew if necessary, and also check radial roller bearing in primary pump housing cover (steps 10.11).


Special Tools:











Return spring for B3 piston:
Transmission = 722.4
Qty. = 20
Wire dia. in mm = 0.85
Length untensioned in mm approx. = 28.0 ± 0.5


Removal and Installation






1. Unscrew bolts.

2. Screw two bolts into the tapped holes (arrows) and in this way withdraw the front cover (10).

Attention:
Do not press off cover (10) with the two bolts. If necessary, slacken cover with screwdriver.


Installation Instruction
Clean sealing face of front transmission cover, check gasket for signs of damage, renew if necessary. The gasket can be used several times as a rule. It must not be coated with sealant.
Coat bolts with non-hardening sealant and tighten to 13 Nm.

3. Take off the two Teflon rings (9).






Installation Instruction

Insert Teflon rings (9) with grease. Ensure that the gap of the rings (arrow) remains together. It may be necessary to again remove the rings and to shape them to a smaller diameter.






4. Mount assembly device (020)
201 589 12 43 00 onto the spring plate (13) and tension until snap ring (15) is exposed. Take out snap ring, release tension of assembly device and remove.

Installation Instruction
Mount assembly device (020) onto the spring plate and tension. Insert snap ring (15) Release tension on assembly device and remove.

5. Take off spring plate (13) and return springs (14) for piston B3.






Installation Instruction
Number of return springs 20.

Note:
Effective Transmission No.25 794 up to Transmission No. approx. 31 000 only 5 return springs were installed. When performing repairs, install 20 return springs together with green ball valve in the front cover.






6. Withdraw piston (12).

Installation Instruction
Check lip sealing rings (16.17); renew, if necessary. The lip seals must be installed so that the sealing lip is facing down the way (direction of arrow).






Fit insertion sleeve (024) 126 589 02 14 00 onto the front cover (10). oil sliding surfaces for the lip sealing rings.

Oil lip sealing rings at the piston. Insert piston (12) so that the stud (on the piston) and the hole (in the front cover) are aligned. Carefully press down piston without tilting it; it may be necessary to move it down with a pin pressed against the outer lip sealing ring (arrow). Take oft insertion sleeve (024).

7. Slacken bolts (8) and unscrew.






8. Take primary pump out of the front cover.

Installation Instruction
Insert M8 x 32 bolts (8) and tighten to 20 Nm.

Note:
Check that ball valve (23) is properly seated. The retaining plate (24) must also be installed when performing repairs to transmissions with a lower Transmission End No. than 316 257 Part No.000 463 00 84 03.

The ball valve is not fitted to the transmissions with a Belleville spring washer in B3 multi-disc brake.






8 Primary pump but
23 Ball valve
24 Retaining plate






9. Remove both pump wheels (3.4) from the pump housing.

Installation Instruction
Oil both pump wheels (3, 4) and place in the pump housing. Insert the pump wheel (4) so that the chamfer (arrow) is facing the radial roller bearing (20).






Attention:
If the radial roller bearing (20) is damaged, the primary pump must be renewed.

10. Check radial seal (6): renew, if necessary.

11. Renew O-ring (7). Insert O-ring into the groove so that it is not twisted in itself.