FITTING-PLUG 6B4112 - Caterpillar

If the service brake fails to stop or slow the machine, push the parking/secondary button in to apply the brake and drag the scraper bowl.The parking/secondary brake will apply automatically if the air pressure drops below 280 kPa (40 psi) in the reservoirs.Loading
1. Reduce travel speed with the service brakes, or retarder, when approaching the cut. The transmission will downshift automatically. 2. Move cushion hitch lever (1) to LOCK DOWN for better control of the cutting edge.3. Move ejector (2) to the rear and open the apron part way. 4. When the transmission downshifts to desired speed, push down the hold pedal.5. Keep the engine rpm in the operating range. Start the cut, and maintain a steady speed, while the pusher makes contact.6. Lower the bowl to an efficient cut depth for the material being loaded.7. The cut should be as deep as possible, and still allow the machine to move at a constant speed, without lugging the engines, or causing excessive tire slip.Decrease depth of cut if the machine or pusher engine lugs, or if the wheels slip. When push loading in rocky conditions, the transmission should be shifted to NEUTRAL and allow the pusher to do the work. Keep the engine speed above 1500 rpm for good hydraulic control response. 8. Use the differential lock to prevent one wheel from slipping. If the wheels slip in soft material, reduce the engine speed.
Do not engage the differential lock with one wheel spinning. Decrease engine rpm, until the wheel stops spinning, before depressing the pedal.
9. If wheel slip continues with differential lock engaged, allow the pushing machine to do the work.10. Gauge the most efficient depth of cut by the depth of the router bits. Use this depth on successive passes. 11. Regulate the apron opening to prevent material from piling in front of the lip or falling out of the bowl. 12. For efficient loading, keep the machine moving in a straight line. Keep the pusher in line with the machine.13. Do not overload the bowl. It lowers efficiency, and can cause machine overloading.14. When the bowl is full, raise the bowl slowly to leave the cut smooth. Close the apron.
Maneuver around large objects to load or unload them. Driving over them could damage the transmission case.
Sand or Loose Material
15. Raise and lower the bowl rapidly to load loose material. When loaded, close the apron as the bowl is raised, to prevent spillage.16. Allow the pusher to help the machine out of the cut area, if necessary. 17. Use the hold valve to maintain constant ground speed in rough terrain. Move the cushion hitch control to cushion ride.18. When ground conditions improve, release the hold pedal until the next higher gear is selected. Depress the hold pedal again to hold the newly selected gear until another upshift is desired. Or, if ground conditions warrant, release the hold pedal and let the transmission upshift to the selected gear.Push-Pull Loading (637E Only)
1. Position the first machine in the