TM 9-2320-272-24-2
4-32. ENGINE INJECTOR TIMING INSTRUCTIONS (Contd)
f. Timing Tool Setup
NOTE
Each of the two dial indicators used in timing the engine must
have a total travel of at least 0.250 in. (6.35 mm).
1.
Position timing tool fixture in injector sleeve (4).
2.
Engage rod (5) of push tube indicator in injector push tube socket.
3.
Install timing tool fixture by tightening knurled holddowns (1) and (2) evenly by hand. Ensure
timing tool fixture is straight on cylinder head (3).
g. Injector Timing
Loosen dial indicator supports on timing tool fixture.
1.
NOTE
Perform steps 2 through 5 for timing procedure 1.
Rotate crankshaft (7) on engine (6) in direction of engine (6) rotation to TDC. Piston travel plunger
2.
will be near full upward position.
Adjust both dial indicators on timing tool fixture to their fully compressed position. To prevent
3.
damage, raise both dial indicators approximately 0.020 in. (0.5 mm), and lock in place with
setscrew.
Rotate crankshaft (7) back and forth to ensure piston is precisely at TDC on compression stroke.
4.
NOTE
Both dial indicators move in the same direction when piston is on
compression stroke.
TDC is indicated by maximum clockwise position of the piston travel pointer. Turn the piston travel
5.
dial indicator face to align zero with the pointer. Lock piston travel dial indicator face with
thumbscrews.
NOTE
Perform steps 6 and 7 for timing procedure 2.
Rotate crankshaft (7) in direction of engine rotation of 90 degrees After Top Dead Center (ATDC).
6.
Piston travel plunger will be near bottom of its travel.
Turn push tube travel dial indicator face to align zero with pointer. Lock face with thumbscrew.
7.
NOTE
Perform step 8 for timing procedure 3.
Rotate crankshaft (7) in opposite direction of engine rotation (backwards) through TDC, then 45
8.
degrees farther to Before Top Dead Center (BTDC) to remove gear train lash.
NOTE
Perform steps 9 through 11 for timing procedure 4.
Turn crankshaft (7) in direction of engine rotation until piston follower rod on timing tool fixture is
9.
in contact with indicator stem.
Move crankshaft (7) very slowly until dial indicator reads 0.0032 in. (0.0812 mm) before zero. Piston
10.
travel piston is now positioned at 19 degrees BTDC.
NOTE
This position is actually 0.2032 in. (5.1612 mm) before "0" because
the dial indicator pointer has rotated twice (over 0.200 in.) (5.08
mm) as the crankshaft was moved to 45 degrees BTDC (timing
procedure 3).
4-240
