Table 4. Troubleshooting Air  flow  restricted. TROUBLE PROBABLE  CAUSE REMEDY Motor  will  not  start. Electrical  power  to  motor  in- Check  that  wall  switch  (if  used)  is  on  and  that  as- terrupted. sociated  fuses  are  not  blown. Check   that   heat   coils   on   magnetic   motor   starter are  not  broken. (See figure 3.) Check  contacts  and  diaphragm  in  pressure  switch assembly. Mechanical  bind  causing  mo- Check  that  electrical  motor  and  flywheel  operate tor  overload. freely. Depress   reset   pushbutton   on   magnetic   motor starter   box. (See figure 1.) Badly  worn  compressors  which  are  pumping  oil may deposit carbon within aftercooler tube and the check  valve.  Clean  or  replace  parts  as  necessary. Motor  is  noisy  or Valves  fouled. Repair   valve   parts   by   cleaning   or   replacement. overheats. Air  flow  restricted. Badly  worn  compressors  which  are  pumping  oil may  deposit  carbon  within  aftercooler  tube  and  the check  valve.  Clean  or  replace  parts  as  necessary. Compressor   runs Dirt  or  dust  accumulation  on Clean baffles on cylinder and tubing by blowing with hot. baffles,  which  acts  as  an  in- air  or  use  a  wire  brush. sulation. V belts slipping. Tighten  V  belts  to  provide  correct  tension  (para- graph  14). Intake mufflers clogged. Clean  intake  mufflers. Oil level low. Add  oil  if  necessary  (paragraph  9). Wrong flywheel rotation. If  flywheel  rotates  against  direction  shown  by arrows,   reverse   rotation   of   motor   by   correcting motor wiring (figure 4). Valves  fouled. Repair   valve   parts   by   cleaning   or   replacement. Air  flow  restricted. Badly  worn  compressors  which  are  pumping  oil may deposit carbon within aftercooler tube and the check  valve.  Clean  or  replace  parts  as  necessary. Compressor   pumps Leakage  in  system. Use  a  soap  solution  to  check  for  leaks  at  all  con- too slowly. nections  and  any  other  suspected  points. Any leakage will be evidenced by bubbles. Valves  fouled. Repair   valve   parts   by   cleaning   or   replacement. Air  flow  restricted. Badly  worn  compressors  which  are  pumping  oil may  deposit  carbon  within  aftercooler  tube  and  the check  valve.  Clean  or  replace  parts  as  necessary. Compressor  will  not Pressure    switch    assembly Check  contacts  and  diaphragm  in  pressure  switch shut  off. defective. assembly. Compressor runs too Leakage  in  system. Use  a  soap  solution  to  check  for  leaks  at  all  con- often. nections   and   any   other   suspected   points.   Any leakage will be evidenced by bubbles. 6