FUEL SYSTEM7-20 TNV IDI Service ManualChecking and Adjusting Fuel Injection Timing• EXAMPLE: If the distance between the two“longer” marks is approximately 2.0 cm and thedistance from the TDC mark is approximately4.0 cm, the answer is approximately 2. Thisindicates there is 10° (2 x 5°) between the TDCmark and the first “longer” mark on the timinggrid. That means the first “longer” mark on thetiming grid indicates 10° BTDC, the second“longer” mark indicates 15° BTDC and the thirdtiming mark indicates 20°. If the answer is 3,that indicates there is 15° (3 x 15°) betweenthe TDC mark and the first “longer” mark andthat the first “longer” mark indicates 15° BTDCwith the second and third “longer” marksindicating 20° BTDC and 25° BTDCrespectively.9. Highlight the timing reference mark on theflywheel housing (Figure 7-25, (2)) or engineback plate (Figure 7-26, (2)). Highlight the TDC(Top Dead Center) mark (Figure 7-25, (1)),(Figure 7-26, (1)) on the flywheel.Figure 7-25Figure 7-2610. Highlight the target timing mark(Figure 7-26, (1)), (Figure 7-27, (1)) on theflywheel timing grid as determined in the FuelInjection Timing Chart below.Figure 7-27Fuel Injection Timing Chart11. Remove all high-pressure fuel injection lines.See Removal of High-Pressure Fuel InjectionLines on page 7-10.12. Turn on all fuel supply valves.10002065A(2)(1)0002142(2)(1)0002066(2)(1)Model CL VM CH VHEngine Speed (rpm) 1500 1800 2000 to2100 2200 2300 to26002700 to30003000 to36003100 to34003500 to36002TNV70 InjectionTiming BTDC±1°- - 15° 16° 18° 21° 20° 21°3TNV70 16° 15° 16° 18° 21° 20° 21°3TNV76 15° 15° 16° 18° 21° 20° 21°
