OM4206 10/06 Maintenance - Section 42 Automatic Lubrication System Page 42-11 INJECTOR OPERATION STAGE 1. STAGE 3. Injector piston (2) is in its normal or rest position. Dis- charge chamber (3) is filled with lu- bricant from the previous cycle. Under the pres- sure of incoming lubricant (6), slide valve (5) is about to open passage (4) leading to mea- suring chamber (1) above injector piston (2). As injector piston (2) completes its stroke, it pushes slide valve (5) past passage (4), cutting off further ad- mission of lubricant (6) to passage (4) and measuring chamber (1).
Injector piston (2) and slide valve (5) remain in this position until the lubricant pressure in supply line (6) is vented. STAGE 2. STAGE 4. When slide valve (5) uncovers pas- sage (4), lubricant (6) is admitted to measuring cham- ber (1) above in- jector piston (2), which forces the lubricant from dis- charge chamber (3) through outlet port (7) to the bearing. After venting, the in- jector spring ex- pands, causing slide valve (5) to move, so that passage (4) and discharge chamber (3) are connected by valve port (8).
Fur- ther expansion of the spring causes the piston to move up- ward, forcing the lu- bricant in measuring chamber (1) through passage (4) and valve port (8) to refill discharge chamber (3). The injector is now ready for the next cycle.