To check or correctly set the fuel injection timing, you need to know:
- the position of the engine crankshaft during the compression stroke in the first cylinder;
- the position of the camshaft of the fuel injection pump at the start of fuel delivery by the eighth section.
To quickly and accurately determine and set the engine crankshaft and the fuel injection pump camshaft to the specified positions, marks are applied to the fuel injection pump body, the automatic injection timing advance coupling, and the rear flange of the driving half-coupling.
In Fig. 2, these marks are designated as «A», «B» and «C» respectively.
The injection timing is correctly set if marks «A» and «B» on the fuel injection pump body and the injection advance coupling coincide, and mark «C» on the rear flange of the driving half-coupling is in the upper position. To set the rear flange 8 to the position where mark «C» takes the upper position according to the lock, it is necessary to unscrew the bolts and remove the cover of the lower hatch of the clutch housing.
Inserting a pry bar into the holes of the flywheel, turn the crankshaft until mark «C» moves from bottom to top.
At this moment, turn the flywheel lock pin 90° and lower it into the deep groove.
Continue turning the crankshaft with the pry bar through the flywheel until the lock enters the flywheel hole.
This will be the upper fixed position of mark «C» on flange 8; at this time, the first cylinder is completing its compression stroke.
Align marks «A» and «B» on the pump body and the injection advance coupling, install the pump and secure it with bolts to the engine block.
Tighten the pump mounting bolts evenly, in several stages, in the sequence shown in Fig. 3.
Without disturbing the mutual alignment of marks «A» and «B» on the pump body and the injection advance coupling, connect the upper end of the driven half-coupling 2 to the front plate 4 with bolts 6 (see Fig. 2).
Set the lock pin into the shallow groove, turn the crankshaft one revolution, install and tighten the second bolt 6.
When the compressor and power steering pump are installed on the engine, it is difficult to see flange 8 (especially the mark on the flange).
In this case, it is more convenient to determine the upper position of mark «C» on the rear flange 8 of the driving half-coupling by the valves.
To do this, remove the cylinder head cover of the first cylinder (Fig. 4) and turn the crankshaft with a pry bar through the flywheel until the intake valve (the front valve on the fan side) begins to close.
Move the lock pin into the deep groove and continue turning the crankshaft until the lock enters the flywheel hole.
This will be the fixed position of the crankshaft at which mark «C» of flange 8 (see Fig. 2) is in the upper position.
After installing the pump on the engine, connecting the control drive, oil supply (drain) pipes, fuel lines and high-pressure pipes, additionally check and refine the injection timing setting.
To do this, move the governor control lever 2 (see Figure 5) to the middle working position and lower it until it stops against bolt 3.
Bleed the engine fuel supply system with the hand priming pump for 2-3 minutes.
Turn the crankshaft half a turn counterclockwise (when viewed from the fan side) and move the lock pin into the deep groove.
Slowly turn the crankshaft in the direction of rotation until the lock enters the flywheel hole.
If the marks on the pump body and the injection advance coupling coincide, the injection timing is set correctly.
If the marks do not coincide, loosen the upper bolt 6 (see Fig. 2) of the driven half-coupling, set the lock pin into the shallow groove, turn the crankshaft one revolution in the direction of rotation, and loosen the second bolt 6.
Turn the injection advance coupling counter to rotation (counterclockwise when viewed from the flywheel side) until the bolts hit the end of the groove in the front plate 4.
Lower the flywheel lock into the deep groove and turn the crankshaft in the direction of rotation until the lock aligns with the hole in the flywheel.
Turn the injection advance coupling by the flange of the driven half-coupling 2 in the direction of rotation until the marks on the pump body and the advance coupling coincide.
Tighten the upper bolt 6, move the flywheel lock pin into the shallow groove, turn the crankshaft one revolution, and tighten the second bolt 6.
Check the accuracy of the alignment of the marks on the pump body and the injection advance coupling one more time in the same way.
After setting and checking the injection timing, start the engine, warm it up to a coolant temperature of 80 °C and use bolt 3 (see Figure 5) to adjust the minimum crankshaft speed, which should not exceed 600 rpm.
