Doors - Lock Cylinders Difficult to Turn

REF. No. 72/40, 88/31

TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERS

DATE: April 1986

SUBJECT:
CLEANING AND LUBRICATING OF HARD TURNING LOCK CYLINDERS MODEL 107, 123, 201

The frequent use of de-icing sprays can wash grease from the lock cylinder and cause them to become difficult to operate. Therefore, lock cylinders should only be treated with lock de-icer (part no. 000 989 07 25). It contains the grease components which lubricate lock cylinders (however, this product is not a grease substitute).

Cleaning and Lubricating Lock Cylinder on Driver-side Door Models 107,123 and 201

NOTE:
The lock cylinders of the driverside door locks on models 124 and 126 and the trunk lid push button lock on models 107, 124 and 126 cannot be disassembled with regular workshop equipment.

1. Remove handle on outside of driver's door (see Service Microfiche Body Assembly Jobs I, job no. 72-240).





2. Drive out roll pin (arrow) and remove turn rod with spring. On model 107, unscrew Phillips screw M5 (Figure 1).

3. Insert master key and remove lock cylinder. On model 201, turn master key 90° to the left or right and remove lock cylinder.

4. Remove key slowly; hold the lock cylinder so that the locking plates do not fall out.





5. Remove locking plates and compression springs one after the other and arrange them in the correct installation order (Figure 2).

6. Clean lock cylinder, compression springs and locking plates individually with pure benzine and then grease them.

NOTE:
If the locking plates are corroded, the complete lock mechanism must be replaced. Individual locking plates are not available for reasons of theft prevention.

Assembly Procedure:

7. Insert compression springs and locking plates in the correct order.





8. Check sealing ring (arrow) for proper fit and correct if necessary (Figure 3).

9. Insert lock cylinder.





10. On locks with water drains (arrow), care should be taken that the drains are open and not clogged with grease (Figure 4).

11. Proceed with installation in reverse order of removal.