5-49. What is indicated when the back of a bearing  shell  contains  a  gumlike  varnish deposit? 1. Excessive  bearing  clearance 2. Normal  bearing  wear 3. Low  operating  temperatures 4. Lack  of  lubrication 5-50. If  the  lower  shell  of  a  journal  bearing is  interchanged  during  installation  with a  plain  upper  shell,  what,  if  anything, happens  to  the  oil  flow  in  the  bearing? 1. It decreases 2. It increases 3. It stops 4. Nothing,  it  remains  the  same 5-51. Bearing  lubrication  is  poorest  when  the engine  is  being 1. overloaded 2. idled 3. started 4. stopped 5-52. What  is  the  purpose  of  motor-driven  lube oil  pumps  used  on  diesel  engines? 1. To  increase  the  pressures  obtainable from  the  engine-driven  pumps 2. To  service  the  engine  gear  training and  bearings  during  normal  operation 3. To  lubricate  the  bearings  before engine   operation 4. To  increase  the  flow  during  engine operation 5-53. In  order  to  check  for  abrasive  elements in  the  lubricating  oil  of  an  engine,  the oil  samples  should  be  obtained  regularly from  which  of  the  following  sources? 1. The  most  accessible  point  in  the  lube oil  system 2. The  lowest  point  in  the  sump 3. The  oil  filter  element 4. The  lube  oil  pump 5-54. What  part  of  a  frictionless  bearing should  you  inspect  for  signs  of  pitting and  surface  cracks? 1. Inner  surface  of  the  inner  race 2. Outer  surface  of  the  inner  race 3. Inner  surface  of  the  outer  race 5-55. Which  of  the  following  actions  may  cause dented  races  in  the  antifriction  bearings that  support  heavy  shafts? 1. The  application  of  too  much  pressure when  the  bearings  are  installed 2. The  application  of  too  much  pressure when  the  bearings  are  removed 3. The  application  of  vibration  to  the bearings  when  the  shafts  are  idle for a long time 4. Each of the above 5-56. A  frictionless  bearing  is  always  replaced when  an  inspection  reveals  which  of  the following   problems? 1. It is difficult to operate by hand 2. It has brinelled races 3. It  operates  noisily 4. It is dirty 5-57. Only  one  race  of  an  antifriction  bearing is made a press fit because it is highly desirable  to  have  the  other  race 1. abrade 2. creep 3. removable 4. unloaded Questions 5-58 and 5-59 are to be judged True or False. 5-58. The only way to tell if a bearing has a  cracked  race  is  by  a  visual  inspection. 5-59. The  best  way  to  determine  if  excessive looseness  exists  in  a  frictionless bearing  is  to  compare  the  bearing suspected  of  being  loose  with  d  new bearing. 5-60. What  is  the  probable  cause  of  looseness in  an  oiled  roller  bearing? 1. Improper   adjustment 2. Improper   installation 3. Abrasives  in  the  oil 4. Faulty  oil  seal 4. Outer  surface  of  the  outer  race 33