Assembling and Coding Ignition Lock Cylinders

Tools Required 

J 41340 Ignition Lock Holding Fixture

1. Determine the tumbler numbers/arrangement:
   1. Place the tip of the key directly over the tip of the illustrated key. See Fig 1.
   2. Inspect that the diagram outlines the key.
   3. Starting with position 1 (open end of cylinder), find and record the lowest level (tumbler number) that is visible.
   4. Repeat the previous step for positions 2-10.
Fig 1: Determining Tumbler Numbers/Arrangement
Courtesy of GENERAL MOTORS CORP.
2. Starting with position 1, insert the tumblers (4) into their corresponding slots in the coded order. See Fig 2.
3. Using your fingers, pull out the side bar (3) until the tumblers fall completely into place.
4. Insert one tumbler spring (2) above each tumbler (4).
5. Lubricate the tumblers using Superlube® GM P/N 12346241 or equivalent.
6. Insert the spring retainer (1) prongs into the slots at the end of each cylinder.
Fig 2: Inserting Tumblers, Tumbler Springs & Spring Retainers
Courtesy of GENERAL MOTORS CORP.
7. Press down the retainer (1) until fully seated in the depression. See Fig 3.
Fig 3: Pressing Down Retainer Until Fully Seated
Courtesy of GENERAL MOTORS CORP.
8. Inspect for proper tumbler installation:
   1. Hold the spring retainer (2) in position. See Fig 4.
   2. Insert the key (1) into the cylinder.
   3. The side bar (3) should drop down flush with the cylinder diameter if properly installed.
   4. Disassemble and assemble properly as needed.
9. Remove the key.
Fig 4: Inspecting Proper Tumbler Installation

10. Secure the cylinder in the J 41340. See Fig 5.
    1. Inspect that the spring retainer is facing up and positioned directly under the punch slots.
    2. Push the cylinder into the J 41340 until butted with the cylinder bezel.
    3. Tighten the holding screw.
Fig 5: Securing Cylinder In J 41340
Courtesy of GENERAL MOTORS CORP.
11. Stake the bezel end of the retainer in place:
    1. Hold the flat side of the punch, part of J 41340, squarely against the face of the cylinder bezel. See Fig 6.
    2. Stake the lock cylinder metal over the retainer corners.
Fig 6: Staking Bezel End Of Retainer In Place
Courtesy of GENERAL MOTORS CORP.
12. Stake the other end of the retainer:
    1. Remove the punch, part of J 41340. See Fig 7.
    2. Rotate the punch, part of J 41340, 180 degrees.
    3. Hold the punch, part of J 41340, squarely against the end of the punch slot on J 41340.
    4. Stake the metal over the other end of the retainer.
Fig 7: Staking Other End Of Retainer
Courtesy of GENERAL MOTORS CORP.
13. Loosen the holding screw.
14. Remove the cylinder from the J 41340.
15. Inspect that the retainer is properly staked. Restake as needed.
16. Lubricate the cylinder retainer slot.
17. Insert the following parts into the cylinder retainer slot:
    • The retainer spring (2). See Fig 8.
    • The retainer (3)
    NOTE: Use a paste type grease, not a spray, for the following step.
18. Lubricate the following parts with GM P/N 12345996 or equivalent as needed:
    • The detent pins (1)
    • The cylinder retainer (3)
Fig 8: Inserting Retainer Spring & Retainer Into Cylinder Retainer Slot
Courtesy of GENERAL MOTORS CORP.