MAINTENANCE N. TRACK TENSION 1. Operate swing, arm, bucket and boom controls until machine is set up as shown in Figure 4.20A. WARNING SUPPORT LOWER FRAME WITH SUITABLE BLOCKS. 2. Measure the sag in the center of the track, be- tween the bottom of the track frame and the track shoe surface. See Figure 4.20B. 3. To increase track tension, set machine as shown in Figure 4.20A and with grease gun inject ex- treme pressure No. 2 grease into idler adjust- ment grease fitting until proper tension is reached. See Figure 4.20C. Perform this pro- cedure on both tracks. 4. To decrease track tension, carefully loosen grease fitting to allow grease to scape. 5.
Tighten grease fitting as shown in Figure 4.20C. FIGURE 4.20A 4 320~350 mm (12.6"~13.8") WARNING SK32004054 GREASE IN TRACK TENSIONING MECHANISM IS UNDER EXTREME PRESSURE AND CAN PEN- ETRATE SKIN CAUSING SEVERE INJURY. KEEP FACE AND BODY AWAY FROM GREASE FITTING AREA. NEVER LOOSEN GREASE FITTING MORE THAN ONE (1) COMPLETE TURN. IF GREASE DOES NOT RELEASE AFTER ONE TURN OF THE FITTING, CALL AN AUTHORIZED KOBELCO SERVICE DEALER FOR ASSISTANCE. FIGURE 4.20B USE CAUTION WHEN ADJUSTING TRACKS 6. Start engine and operate the travel motor for the track being adjusted, back and forth. Re- check track tension and adjust if needed. 7. Perform steps 1 through 6 on the opposite track if needed.
TORQUE GREASE FITTING TO 45 lbs-ft (6 kgf-m) FIGURE 4.20C 4-20 SK210(LC)/SK250(LC)–VI Dynamic Acera OM, 09/00 Rev.2