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Flex Disc - (Front) Must Be Inspected Every 30,000

90mercedes04
TO: OUR MERCEDES-BENZ PASSENGER CAR

DATE: August 1990 (supersedes MBNA 41/1, Apr. '90)


SUBJECT: INSTALLING FLEX-RESISTANT DISC ON FRONT DRIVE SHAFT MODEL 124
REF. NO. MBNA 41/1a
The flex discs, particularly the front flex disc (transmission-side), may be subject to very high dynamic and thermal loads depending on driving style. Therefore they must be inspected every 30,000 on all models as a part of routine maintenance.

Figure 1:




Damaged or cracked flex discs must be replaced. In vehicles with 90 mm diameter flex discs (up to and including model year 1989), the rear (axle side) flex-resistant disc (B, Figure 1) may be installed at the front (transmission-side) instead of the softer flexible disc (A), since disc B can withstand more abuse.

Note: Flex-resistant disc with 90 mm bolt circle may not be installed on vehicles with 100 mm bolt circle discs.

Figure 2:




Prooedure

1. Remove drive shaft (41-050).

2. Remove hex head bolts (11, Figure 2).

3. Remove old flex disc.

4. Replace centering sleeve if excessive wear is present.

Figure 3:




5. Press centering sleeve 3.0 mm deeper (see note) into three-arm flange.

Note: Previous press-in dimension (a, Figure 3) from face of sleeve to flange was 30 mm, new press-in dimension is now 27 mm.

6. Ensure that cavity of centering sleeve is conpletely lubricated with an approved multi-purpose grease (see latest Approved Service Products S. I. in group 00).

7. Install new flex-resistant disc.

8. Replace hex head bolts and selflocking hex nuts. Adhere to specified tightening torques as listed service microfiche.

9. Reinstall drive shaft.

10. Tighten clamping nut to 30-40 N-m.


Part Name Part Number


Flex-resistant disc, repair kit 124 410 02 15
Centering sleeve 124 410 07 32


In Case of Warranty:

Time Allowance see latest edition of Time Guide for:
Driveshaft Flex Disc - Transmission side, Repl.

Damage Code
41008 Centering sleeve, drive shaft; worn out 08
41033 Flex disc, drive shaft; worn 10
loose 38