4-52. When the plunger of the injection pump of a diesel engine is stuck, it usually causes  which  of  the  following  conditions? 1. Engine  failure 2. Excessive  fuel  consumption 3. Increase  in  engine  temperature 4. Failure  of  a  cylinder  to  fire 4-53.  A  binding  plunger  test  is  being  performed. What kind of trouble is indicated by a sluggish  return  of  the  plunger? 1. A  broken  plunger  spring 2. A  sticky  plunger 3. A  nicked  plunger 4. A  scored  plunger 4-54.  In  trying  to  loosen  a  stuck  fuel  oil injector  plunger,  you  should  soak  the plunger and barrel in which of the following   fluids? 1. Clean  diesel  fuel 2. Lubricating  oil 3. Cleaning   solvent 4. Unleaded  gasoline 4-55.  You  are  cleaning  a  Bosch  fuel  injection pump plunger. What should you do after rinsing it in fuel oil and blowing it dry? 1. Examine  the  plunger  for  defects 2. Reassemble  the  pump  assembly 3. Place  mutton  tallow  on  the  plunger 4. Wipe the plunger with a mild abrasive 4-56. Which of the following materials should NOT be used to free up the plunger and bushing  to  a  G.M.  unit  injector? 1. Jewelers'  rouge 2. Mutton  tallow 3. Clean  fuel  oil 4. Compressed  air 4-57. In a diesel engine fuel system, what is the  function  of  the  fuel  control  rack? 1. To  control  vaporization  of  fuel 2. To  remove  impurities  from  the  fuel 3. To  meter  the  fuel  injected  at  each stroke 4. To  prevent  jamming  of  the  fuel injector   plunger 4-58. Which  of  the  following  conditions  causes an engine fuel oil control rack to stick? 1. End play 2. Normal  wear 3. Gear  backlash 4. Dirt  in  the  mechanism 4-59. What effect, if any, may backlash in the control  rack  have  on  engine  performance? 1. High  exhaust  temperature 2. Low  firing  pressures 3. Variations  in  speed 4. None 4-60. Backlash  in  the  fuel  control  system  is often  caused  by  which  of  the  following parts? 1. Jammed  control  rack 2. Scored  pump  plunger 3. Distorted  pump  bushing 4. Worn  control  sleeve Learning Objective: Discuss the opera- tional  characteristics  of  fuel  injection equipment and engine controls. Recognize symptoms  of  fuel  injection  troubles,  as well as their causes, and indicate corrective  measures  that  may  be  required. Question 4-61 is to be judged True or False. 4-61. Improper  seating  of  the  exhaust  valves may cause symptoms similiar to improper timing  of  the  engine  fuel  injection system. 4-62. Late timing of fuel being injected into a cylinder may be indicated by which of the following   conditions? 1. Engine   detonation 2. Injection  pump,  leakage 3. High  exhaust  temperature 4. Low  exhaust  temperature 4-63. Which of the following factors may be the cause for a Bosch fuel injector pump to go out of timing? 1. A  broken  spring 2. A stuck plunger 3. A  worn  pump  camshaft 4. An  eroded  spill  port 4-64. Which of the following corrective measures could you use to reduce the number  of  engine  governor  difficulties? 1. Reduce  the  engine  speed 2. Increase  the  engine  load 3. Use  clean  oil 4. Adjust  the  fuel  linkage 27