TM  10-3930-638-24&P 3-3. ENGINE TROUBLESHOOTING (cont) MALFUNCTION TEST  OR  INSPECTION CORRECTIVE ACTION 5.  ENGINE  STALLS  FREQUENTLY  OR  DOES  NOT  DEVELOP  FULL  POWER Step 1. Check for proper engine timing and valve tappet clearance adjustment (para 3-5a). a. If engine timing and valve tappet clearance adjustment is not okay, adjust (para 3-5a). b. If engine timing and valve tappet clearance adjustment is okay, proceed to step 2. Step 2. Check fuel injection pump timing and speed adjustments (para 3-5a(3)). a. If fuel injection pump timing and speed adjustments are not okay, adjust as described in paragraph 3-5a(3). b. If fuel injection pump timing and speed adjustments are okay, proceed to step 3. Step 3. Perform compression test of each cylinder (para 3-3 MALFUNCTION 7). If  compression  test  is  satisfactory,  test  fuel  injector  nozzles  before  reinstalling  on  engine  (notify general  support  maintenance)  (para  4-3a).  If  fuel  injector  test  is  satisfactory,  check  for  camshaft installed one tooth out of time or a defective fuel injection pump (notify general support maintenance)  (para  4-2g  or  4-3b). 6. ENGINE KNOCKS Step 1. Step 2. Step 3. Step 4. Start engine and listen for chucking or pounding sound at low speed, which disappears as engine speed is increased. a. If chucking or pounding sound is heard at low speed and disappears as engine speed is increased, check flywheel for looseness or damage (notify general support maintenance) (para 4-2e). b. If chucking or pounding sound is not heard, proceed to step 2. Start engine and listen for a sharp metallic sound which increases as engine speed increases. Crack (open) the injector line to each cylinder, one at a time, to check if the knock stops or decreases. a. If the knock stops or decreases, check for defective rod bearing on affected cylinder (notify general support maintenance) (para 4-2f). b. If the knock increases, check for defective piston pin (notify general support maintenance) (para  4-3. c. If knock is not heard, proceed to step 3. Start engine and listen for a thudding sound which increases as engine speed increases. a. If thudding sound is heard which increases as engine speed increases, check main bearings for wear or damage (notify general support maintenance) (para 4-2d). b. If thudding sound is not heard, proceed to step 4. Start  engine  and  listen  for  one  thudding  sound  when  increasing  engine  speed  and  one  thud  when decreasing speed. Check camshaft and crankshaft for excessive end play (notify general support maintenance) (para  4-2g  and  4-2d). 3 - 4