Spring Strut Shock Absorber Assembly: Overhaul

WARNING: It is essential to use Special Tool inserts (31 3 368 ) and (31 3 357). Failure to use protective inserts exposes the risk of the spring detaching from the spring retainers during the tensioning/relieving operation. Never tighten or untighten Special Tools with an impact tool.

WARNING: Coils of coil spring must be located completely in recess of Special Tools (31 3 357) with protective insert (31 3 368) when tensioned. Compress coil spring only until stress on piston rod is relieved.

1. Remove spring shock absorber assembly. See SPRING STRUT SHOCK ABSORBER ASSEMBLY . Clamp Special Tool (31 3 341) in vise. Position Special Tools (31 3 357) with protective inserts (31 3 368) from above on Special Tool (313 3 341) until locking pins can be felt and heard to snap into place. See Fig 1. Check that Special Tools (31 3 357) are securely seated and correct as necessary.
2. Clean coil spring to remove course dirt and take up with Special Tools (31 3 357) and (31 3 341). See Fig 2.
3. Starting from a stud, mark installation position of support bearing on spring strut shock absorber. See Fig 3. Compress coil spring until stress on piston rod is relieved.
4. Release nut (gripping piston in the process). See Fig 4. Remove shim and support bearing with spring pad. Remove spring strut shock absorber with thrust washer, damper and lower spring pad sideways from tensioned coil spring. Remove thrust washer, damper (1) with protective tube and lower spring pad (2). If necessary, relieve tension on coil spring.
5. To reassemble, check lower spring pad (2). If necessary, replace and position on spring plate. Check damper (1) with protective tube, if necessary replace and attach to piston rod. See Fig 5. Attach thrust washer to piston rod.
6. If necessary, carry over marking from spring strut shock absorber to new component. Insert spring strut shock absorber in tensioned coil spring and align to end of coil spring using lower spring pad. See Fig 6.
   NOTE: Ensure end of coil spring is precisely seated in lower spring pad. See Fig 7 and Fig 8 .
7. Check support bearing and replace as necessary. Attach support bearing to piston rod. Use lower spring pad to align support bearing to end of coil spring.
8. Attach shim to piston rod. Replace self-locking nut and screw on as far as possible to avoid damaging the piston rod when relieving tension on the coil spring. Align support bearing by way of a stud to marking on spring strut shock absorber. See Fig 3.
9. Relieve tension on coil spring slightly. Tighten down nut (gripping piston rod in the process). See Fig 4. Ensure lower and upper coils of coil spring rest completely in recess of spring plate or support bearing. Fully relieve tension on coil spring.

Fig 1: Clamping Special Tool (31 3 341) In Vise

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Fig 2: Placing Upper & Lower Coils Of Coil Spring Between Spring Retainers

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Fig 3: Marking Installation Position Of Support Bearing

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Fig 4: Removing Spring Strut Shock Absorber Nut

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Fig 5: Checking Damper With Protective Tube

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Fig 6: Inserting Spring Strut Shock Absorber In Tensioned Coil Spring

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Fig 7: Ensuring End Of Spring Is Seated In Rubber Mount (1 Of 2)

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Fig 8: Ensuring End Of Spring Is Seated In Rubber Mount (2 Of 2)

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