1942 - 1947 Chevrolet Shop Manual



1-30

First-Hold the key decoder in left hand, and insert the key from the right side. Second-Read the code from head of key to end, from positions 1 to 6. The depths cut are shown by the indicators under each position number, Fig. 57. Third-An indicator reaching into the copper strip indicates depth "C": indicator reaching into the nickel strip indicates depth "N"; in black strip "B", and in yellow strip "Y". Fourth-The code of the key illustrated in the key decoder reads- 1-2-3-4-5-6 B-C-B-Y-N-Y CAUTION-The tip of the indicator must split the colored strip. Save the gauge key, furnished with each key decoder, to frequently check the key decoder. Gauge key is cut Y-B-N-C-C-C. How to Determine Code of Key without Decoder 1. Lay the key on the diagram, Fig. 58, with the bottom of the key flush with the edge of the drawing, head and point carefully lined up.	C-Copper N-Nickel B-Black Y-Yellow
		First-Hold the cylinder in the left hand with the head of the cylinder away, Fig. 59, and, starting at the head of the cylinder, insert the tumblers in their proper slots in the order called for by the code, ribbed side toward you, and long point down. Second — After all
		tumblers are in place,
	Fig. 59-Holding Lock Cylinder with Head Away	check for correctness
	with the code. Fig. 60. Then, press the tumblers down with one finger, Fig. 61. Third-Insert one tumbler spring in the space provided above each tumbler. Fig. 62. CAUTION-If the springs are tangled do not pull them apart-unscrew them.
		Fourth — Reverse the lock cylinder in left hand so that the head of the cylinder is now toward you. Insert the spring retainer, Fig. 63, so that one of its six prongs enters into each of the springs, and the two large end prongs slide into the slots at either end of the cylinder. Press the retainer


	Fig. 40 Fig. 61	down with one finger

Fig. 58-Key Decoding Diagram 2. Read the code in letters C-N-B-Y from head of key to the top, from positions 1 to 6 inclusive. As each depth is determined, write that letter in the blank space provided above the position numbers (1-2-3-4-5-6). 3. With the key properly lined up on the diagram, all cuts that show in the first section are to be marked "C". Cuts that fall in the first black section, mark "N". Cuts that fall in white section, mark "B". Cuts that fall in second black section, mark "Y". How to Assemble a Lock Cylinder The letters (C-N-B-Y) which have been written above the cutting positions indicate the different color tumblers which are to be dropped in each tumbler slot of the lock.	and in that position insert the assembly into the checking and staking tool, Fig. 64.
		Fifth-To Check. Insert the proper key, and rotate cylinder clockwise about 1/8 turn. If lock is properly assembled the cylinder will turn, otherwise the bar will NOT be released and the cylinder cannot be rotated. In this case remove and reassemble the tumblers properly.
	Fig. 62-Installing Tumbler Springs	Sixth-If cylinder rotates, return it to the
	original position and remove the key. Place cylinder and key in vise, using leather or wood on each side to prevent damage to cylinder, Fig. 64.