NOTE: The push cat operator should be extremely cautious in NOT hitting the rear scraper tires with the dozer  blade. The  push  cat  operator  must  ensure  that  the reinforced section of the dozer blade is centered on the scraper rear push block. Additionally, the push cat operator must be alert to turns made by the scraper that might cause the push cat to apply unequal pushing force. This could result in the dozer blade contacting the scraper  rear  tires  or  causing  the  scraper  to  jackknife. The  push  cat  should  continue  pushing  after  the  scraper has a full load to give the scraper a boost in leaving the cut. Hauling After the scraper is fully loaded and has reached the haul road, the operator should raise the bowl to travel height and proceed to the fill or dump area in the highest gear  range  practicable.  The  bowl  travel  height  should be no higher than needed to clear any obstacles on the haul road. A low bowl height allows better control of the scraper by keeping the center of gravity low and preventing the loss of time needed to lower the bowl, as the scraper approaches the fill area. The best bowl height is the height at which the bowl must be in when the load is spread. When  hauling  down  steep  grades,  lower  the  bowl until the blade drags to slow the scraper down. When traveling over a slippery haul road, keep the cutting edges as close to the road as possible to allow for a fast emergency stop by dropping the bowl. When traveling over haul roads, avoid holes and large obstacles that may damage the scraper tires. When making sharp turns, allow enough clearance for the length and width of the scraper to keep the scraper wheels on the road. Spreading or Unloading When approaching the fill area, lower or raise the scraper  bowl  to  the  depth  of  fill  desired.  The  speed  of the scraper must also be adjusted for this depth, such as a high speed for a thin spread or a slower speed for a deep  spread. To start spreading, raise the apron by engaging the apron control lever to allow the material to fall out of the bowl. The size of the apron opening depends mainly upon the depth of the spread and type of material being spread;  for  example,  a  thin  layer  of  free-flowing  sand needs a fairly small apron opening and a high travel 10-22 speed, while a thin spread of wet clay will need a larger opening and a slower travel speed. After  the  apron  opening  has  been  adjusted  and  the dirt flowing through the opening lessens, engage the ejector lever to finish unloading the scraper bowl. When the scraper is empty, engage the ejector lever to return the ejector to the rear of the bowl and lower the apron. Unloading techniques are as follows: .  Keep  the  scraper  moving  while  unloading. Stopping  when  unloading  on  soft  fill  costs  production time  by  needless  shifting  and  the  possible  miring  down of the scraper. l Always make an even spread, so the next trip will not be rough. . If possible, when traveling out of a fill, pass back over the area you have just filled to compact it with the large  scraper  tires. Returning to the Cut After the scraper is unloaded and has reached the haul road, return to the cut as soon as possible. When returning to the cut, carry the scraper bowl high enough to avoid any haul road obstacles, yet low enough for safe handling of the scraper. Carrying the bowl low allows for quick lowering of the bowl to stop the scraper in the event of an emergency. Allow plenty of room for the rear  wheel  of  the  scraper  to  avoid  obstacles  when making tight turns, and maintain a safe speed for the condition of the haul road. WORKING DIFFICULT MATERIALS Special operating techniques are required when performing scraper operations in difficult materials, such as wet or sticky material, loose sand or gravel, and large  objects. Wet and Sticky Materials When unloading wet and sticky material, do not try to spread the material too thin. Always keep the bowl high enough to allow the material to flow back under the scraper. Open the apron wide enough to allow an easy flow out of the bowl, Bring the ejector forward with short, snappy movements of the ejector control lever to shake the material loose from it. Allow a little time between each ejector movement to avoid compacting the  material  between  the  apron  and  ejector.  In  some cases,  shifting  the  ejector  between  forward  and  reverse