Dynamic Timing (Engine Running)

Correct timing specifications vary with cetane value of engine fuel. Before performing timing test, determine cetane value as follows:

1. Obtain a small fuel sample from injection system. Temperature of fuel must be 75-95°F (24-35°C) to obtain accurate results.
2. Fill hydrometer container included with Dynamic Timing Meter (078-00100) with fuel until hydrometer floats. Spin container gently to break surface tension of fuel.
3. Read number at lowest point of fuel level in hydrometer. Compare reading to DIESEL FUEL CETANE VALUES  chart to determine Cetane value.
   DIESEL FUEL CETANE VALUES
   
   

   Hydrometer Reading	Cetane Value
   .837	50
   .846	47
   .849	46
   .858	43
   .862	42
   .876	38

4. Start and warm engine to normal operating temperature. Coolant temperature MUST be 192-212°F (89-100°C) when performing dynamic timing procedure. Stop engine and install magnetic pick-up probe of Dynamic Timing Meter (78-0100) into timing pointer probe hole. See Fig 1 .
   Fig 1: Magnetic Pick-Up Probe Installation

   
5. Remove No. 1 cylinder glow plug. Install luminosity probe in place of glow plug and tighten to 12 ft. lbs. (16 N.m). See Fig 2 . Connect photocell over luminosity probe and connect to timing meter. Connect meter to battery and adjust offset on meter.
   Fig 2: Luminosity Probe Installation

   
6. Raise and support rear wheels. Place transmission in Neutral and start engine. Using Throttle Controller (014-00302), set engine speed at 1400 RPM with no accessory load. Read injection timing on meter.
7. If injection timing is not within 2° of value indicated in DYNAMIC INJECTION TIMING SPECIFICATIONS  chart, timing must be adjusted. If timing is not within specifications, stop engine and loosen pump retaining nuts (keeping nuts snug).
8. Using pump rotator, rotate pump clockwise to retard timing or counterclockwise to advance timing (as viewed from front of engine). Tap rotator with rubber mallet as needed to rotate pump.
9. Moving timing mark .030" (.75 mm) is equal to 2° of timing. Retighten nuts. Recheck timing using meter. Repeat step 8 as needed to obtain correct timing. Remove timing meter and other test equipment. Reinstall glow plug using anti-seize compound on threads.