Viscous Coupling: Service and Repair

NOTE: Check that the parking brake is not set and that no gear is engaged.

NOTE: Special tools: 999 5972, 999 5010, 999 5089, 999 5212, 999 5304, 999 5504, 999 5561, 999 5652, 999 5653, 999 5658, 999 5971

Removing Torque Tube





Raise The Car

Removing propeller shaft

NOTE: Follow instructions on positioning lift arms carefully according to Towing, changing wheels and rolling road/wheel spinner test.

Mark Propeller Shaft CV Joint In Relation To Viscous Coupling Flange.

NOTE: Carefully note the length and position of screws on the propeller shaft CV joint. The propeller shaft may have been balanced with balancing screws. With regards balancing screws, see Specifications page 2(Standard screw for front and rear propeller shaft CV joint and balancing screw for rear joint).

- Remove propeller shaft screws. Use counter- hold 9995561
- Move propeller shaft to one side and support





Removing Torque Tube
- Position a mobile jack, 998 5972, lightly under the torque tube
- Remove the screw holding torque tube to car body.
- Lower the torque tube so that the final drive housing is resting on the lower section of the rear axle member.
- Remove mobile jack





Marking Flange
- Mark flange in relation to the end of the viscous coupling shaft.
- Remove drive flange. Use counterhold 999 5652. Pull the flange off the shaft.
- Use a separator if the flange is stuck 999 5304.





Removing Torque Tube
- Remove four screws holding torque tube to final drive. Pull off torque tube, turning it to release it from the fuel tank.
- Keep the washer from the viscous coupling shaft.
- If the bearing in the torque tube is not being replaced, continue with removing viscous coupling.
- Replacing bearing in torque tube.





Pressing Out Bearing
- Use drift 999 5010 as a support for torque tube and press tool 999 5212.





Pressing In Bearing
- Use drift 999 5858. Press in bearing to its stop in torque tube.

NOTE: For installation of torque tube, continue with installing viscous coupling.

Replacing Rear Pinion Seal And Viscous Coupling





Removing Viscous Coupling
- Remove viscous coupling from final drive Mark the position of the viscous coupling flange in relation to the final drive flange.

NOTE: If replacing the viscous coupling it is not necessary to mark up the flange.

- If replacing just the viscous coupling, continue with Measuring flange, viscous coupling and Balancing procedure Drive/Propeller Shafts, Bearings and Joints
- Then continue with installing torque tube.





Marking Flange
- Mark flange in relation to the end of the pinion
- Remove flange nut. Use counterhold 999 5652.





Removing Flange
- Use a separator if it is stuck 999 5304.
- Put a container under the car to collect oil draining from the final drive.





Checking Flange
- Check flange seal face carefully. Replace flange if necessary.





Removing Pinion Seal
- Use separator 999 5069.





Check
- Check that no seal residue remains.





Installing Seal
- Lubricate sealing ring lip with Volvo wheel bearing grease P/N 1161241-3.
- Install seal on drift 999 5653 (on the side of the tool marked 1031-1165).
- Press seal into its seating. Use press tool 999 5504.





Installing Flange To Pinion

Install Drive Flange
- If reinstalling the old flange, install according to markings.
- Use press tool 999 5504. Use a new, lubricated nut. There must be no axial play.

NOTE: If installing a new flange, measure according to Measuring flange, viscous coupling and Balancing procedure. Refer to Drive/Propeller Shafts, Bearings and Joints. Service and Repair

- Tighten to 180-200 Nm (132.8-147.6 ft.lb.). Use counter- hold 999 5652.

NOTE: Do not exceed a tightening torque of 200 Nm (147.5 ft.lb.). The forces on the pinion bearing may become too great, causing it to seize.

- If reinstalling the old flange, continue with installing viscous coupling.





Installing Viscous Coupling
- Check that the flange and viscous coupling mating surfaces are absolutely clean.
- Align viscous coupling as marked.
- Use new screws. Tighten crosswise in stages until the viscous coupling flange is in full contact. Tighten crosswise to 50 Nm (37 ft.lb.).
- If reinstalling the old viscous coupling, continue with installing torque tube.

NOTE; If installing a new viscous coupling, measure according to Measuring flange, viscous coupling and Balancing procedure,Drive/Propeller Shafts, Bearings and Joints After measuring continue installing flange to viscous coupling.





Installing Torque Tube
- Install torque tube. Lightly tighten the four screws crosswise, then tighten to 50 Nm (37 ft.lb.)

NOTE: Check that the mating faces on the final drive housing and torque tube are clean and that the washer is in place on the viscous coupling shaft.





Installing Flange To Viscous Coupling
- Install flange to viscous coupling shaft as marked Use a new nut. Tighten to 180 Nm (132.8 ft.lb.). Use counterhold 999 5652.

NOTE: If the old flange has been installed as above, continue with installing propeller shaft.





Checking Runout

Check axial runout on the flange and locating pin

NOTE: Only needs to be carried out if the flange has been replaced.

NOTE: Ensure that the measuring faces are absolutely clean.

- Secure plate 999 5971 in the torque tube and magnetic holder with dial gauge on plate.
- Check locating pin radial runout, maximum value 0.05 mm (0.00197").
- Check flange axial runout, maximum value 0.05 mm (0.00197").
- If values are exceeded move the flange a quarter turn at a time.

NOTE: Always use a new nut.

- Check runout again until the correct values are obtained.
- Remove measuring equipment and plate 999 5971.





Installing Propeller Shaft

Install Propeller Shaft To Flange

NOTE: Install propeller shaft as marked. Use new screws of the same length. Reinstall screws in the same positions.

- Check that viscous coupling and propeller shaft flange mating surfaces are clean.
- Tighten screws crosswise to 8 Nm (5.9 ft.lb.). Then tighten crosswise to 30 Nm (22.1 ft.lb.). Use counterhold 999 5561.
- Start tightening with the same screw both times.