CLIP 5349791 - Caterpillar

C Replacing The Lamp In The 6V3136 Photo Pickup
If the lamp in the photo pickup has been checked and found defective, it can be replaced with a new 6V3061 Lamp. To do this, the photo pickup must be disassembled as follows. 1. Remove two screws (1) from pickup cap (2). Pull the pickup halves apart, being careful not to let lens (3) fall out of cover (4). Slide cover (4) completely off inner body (5) of the pickup.2. Hold cap (2) and bend inner body (5) back so lamp socket (6) can be removed. Pull the lamp socket completely out of the inner body, being careful not to damage any of the wires. Unscrew the lamp and install a new 6V3061 Lamp. Put the lamp and socket back in position in the inner body.3. Carefully remove lens (3) from cover (4) by turning the cover upside down. Red lens retaining washer (7) may also come out of cover (4). Clean lens (3) before installation back in cover (4). 4. To install lens (3), hold cover (4) vertical, so the end with screw holes (A) is up and the other end is down. Install red washer (7) in cover (4), and turn the washer as necessary so it is against the bottom end of the cover. Pick up lens (3) and hold it over the cover so the curved side of the lens is down. Drop the lens into the cover so it is against the red washer. Make sure the curved side of lens (3) is toward the red washer. If not, use a pencil to turn the lens. While holding cover (4) in a vertical position, slide inner body (5) into cover (4). When inner body (5) is in position in cover (4), put cap (2) in place on cover (4) and install screws (1). Make sure the curved side of the lens is toward the red washer. If it is not, disassemble the pickup and put the lens in the correct position.5. To test the lamp, connect the pickup to the multitach. With the light toward an object about 1 ft. (.3 m) away from the end of the pickup, the spot of light on the object should be a small circle approximately .5 in. (12.7 mm) in diameter straight out from the end of the pickup. If the light is not satisfactory, a different 6V3061 Lamp should be installed in the pickup.Result Of Incorrect Connection Of Power To Earlier Multitachs Without Fuses (Multitachs Built Before May 1, 1981)
All multitachs built after May 1, 1981, have miniature fuses soldered in place on the input power lines. These fuses protect the multitach from damage due to incorrect power connections and shorted tachometer generators. Earlier multitachs that have been damaged due to incorrect connection of power will not operate or show any display. It may be possible to repair the damage to the multitach using the following procedure; however, repair should be attempted only by personnel familiar with