20.4Fuel injection timing adjustment

20.4.1Driving Part Structure of Fuel Injection Pump

(1)Current production engine model

•Structure of driving parts: A driving gear is installed directly at the edge of the fuel injection pump cam shaft.

•Fuel injection timing adjustment.

Direct injection system engine N-series Swirl system pre-combustion engine

Swirl pre-combustion system engine (Not including N-series)

FID method, adjusted by turning the fuel injection pump to the right or lefthand around the fuel injection pump cam shaft.

FID method, adjusted by changing the shim thickness between the body of the fuel injection pump and the pump case. YE0301

N-series (Swirl pre-combustion system)

1)End nut

2)Fuel

(2-1)Direct injection system engine

•Driving part structure: the fuel injection pump coupling is fitted to the end of the fuel injection pump cam shaft. After the FIC is adjusted, the fuel injection pump coupling is locked to the pump body not to turn the fuel injection pump cam shaft using the lock bolts. (Adjusted by fuel injection pump manufacturing plant of Yanmar)

•Fuel injection timing adjustment: Adjusted by using the FIC fixed method.

(2-2)Swirl pre-combustion system engine i)Attach the driving gear to the couping temporarily and fix the gear so that it does not turn using the jig.

•Driving part structure: The coupling is attached to the end of the fuel injection pump cam shaft (shrinkage fit), the driving gear is attached to the coupling with bolts.

•Fuel injection timing adjustment: Adjusted by a FIC fixed method.

(Alignment mark for driving gear: No.1 cylinder at top compression position of engine) ii)Turn the fuel injection pump cam shaft to the clookwise viewed from the gear side and examine the FIC position of the No.1 cylinder. iii)Turn the fuel injection pump cam shaft to the clockwise further more (fuel injection timing x 1/2 deg.) to decide the position of the fuel injection timing on the fuel injection pump. After that, fix the driving gear to the coupling with 4 bolts. (Adjusted by fuel injection pump manufacturing plant of Yanmar)

3 Bolt (M7) tightening torque (not apply lub. oil): 13.7 ± 2 Nm {1.4 ± 0.2 kgm}

1)No.1 cylinder6)Fuel injection pump driving gear fixed pin hole (Tool to prevent turning)

2)Fuel injection timing shim (0.8 mm regularly)

3)Gear attaching bolt (4-M7)7)Gear case

4)Coupling (Shrinkage fit)8)Aligning mark

5)Fuel injection pump driving gear9)Cam shaft driving pin hole (Coupling, for jig)

(2-3)Swirl pre-combustion system engine (2D68E-N, 3D68E-N, 3D74E-N only)

•Driving part structure: Driving gear is attached directly to the end of the fuel injection pump cam shaft as in the current production model, however, the method for marking to install on the engine differs from the current production model.

•Fuel injection timing adjustment: Adjusted by the FIC fixed method i)Using the marking tool, turn the fuel injection pump cam shaft to the clockwise viewed from the gear side to find the FIC position (A°) for the No.1 cylinder. ii)Turn the cam shaft further more to the clockwise from the FIC position (B°: fuel injection timing of engine x 1/2 deg.), decide the position for fuel injection timing on the fuel injection pump and mark the installing mark on the engine. The position for the installing mark is 45 ± 1 degrees from the center of the fuel injection pump with the fuel injection timing adjusting shim. (Had been adjusted by pump manufacturning plant of Yanmar)

20.4.2Fuel Injection Timing Adjustment

(1)Installing the fuel injection pump in factory (1-1)Direct injection system engine

Procedure i)Align the fuel injection pump with the mark shown in figure 7 and install on to the gear case. a Align the mark on the fuel injection pump with the center mark (5th mark from the top) on the gear case. k Before installing the fuel injection pump, confirm that the FIC lock is still attached. The correct fuel injection pump cam shat on the assembly line side does not turn. Do not use the pump if there is the problem. k The marks on the gear case and the fuel injection pump have no relation to the fuel injection timing and are the same on all engine models. The installing angle for the pump is fixed (all the engines are same). ii)Attach the fuel injection pump driving gear to the fuel injection pump coupling to allow rotating freely on its outer surface without bolt fixing. iii)Align the timing mark of each gear, crank, idler, cam and fuel injection pump drive gear and install them. k When aligning the timing marks, put the piston for the No.1 cylinder in the top compression position, align the letters on the gears and assemble. No.1 cylinder is from the flywheel side. iv)Align the crankshaft with the FIC fuel injection angle (B.T.D.C). To reduce the deviation in the fuel injection timing, the equivalent crank angle is determined by measuring the piston stroke of the cylinders noted below and calculating the average value. The piston stroke is determined by measuring the T.D.C. when the piston is in the top position.

[Piston stroke measuring cylinder No.]

•3-cylinder engine: No.1, 3 cylinders

•4-cylinder engine: No.1, 2 cylinders v)Keeping the gear backlash fix the fuel injection pump driving gear to the fuel injection pump coupling by automatically tightning the 2 bolts (marked E) in the factories.

NOTE: The procedures described in iv) are performed automatically in the factories.

3

Bolt tightening torque (not apply lub. oil): 34.32 ± 1.96Nm {3.5 ± 0.2kgm} vi)Tighten the remaining 2 fixing bolts for the fuel injection pump driving gear by hand.

3 Bolt tightening torque (not apply lub. oil): 34.32 ± 1.96Nm {3.5 ± 0.2kgfm} vii)Remove the FIC lock bolt. (See figure 3.) The fuel injection timing adjustment is completed.

After removing the FIC lock bolts, do not separate the fuel injection pump coupling and the fuel injection pump driving gear. If they are separated, this will confuse the FIC setup and it will be necessary to adjust the fuel injection timing from the beginning.

If the fuel injection pump should have to be removed the fuel injection pump, loosen the end nuts to do it.

(1-2)Swirl pre-combustion system engine

Procedure i)Install the fuel injection pump/governor assembly (pump case integrated in gear case) to the body of the engine. (Figure 4) k Check to see that the fuel injection pump coupling and driving gear are firmly attached before installing them to the engine body. Do not use them if loose. ii)Align the timing mark for the crankshaft, idler, camshaft, and the fuel injection pump driving gear and then assemble them. a When aligning the timing marks, put the piston for the No.1 cylinder in the top compression position, align the letters on the gears and assemble. No.1 cylinder is from the flywheel side.

1)Fuel injection pump driving gear

2)Cam gear

3)PTO gear

4)Crank gear

5)Directon of revolution

6)Lub. oil pump gear

7)Ldler gear k The fuel injection timing is set (FIC) by aligning the timing mark of the gear train. Do not adjust with the FID method. k Do not separate the fuel injection pump coupling and the fuel injection pump driving gear. If they are separated, this will confuse the FIC setup and it will be necessary to adjust the fuel injection timing from the beginning.

(1-3)Swirl pre-combustion system engine (2D68E-N, 3D68E-N, 3D74E-N only)

Procedure i)Align the fuel injection pump with the mark shown in figure 11 and install on the gear case. a Aligning the marks on the fuel injection pump and gear case is the same for all these models. ii)Align the timing marks of each gear, crank, idler, cam, and fuel injection pump driving gear and install them. a When aligning the timing marks, put the piston for the No.1 cylinder in the top compression position, align the letters on the gears and assemble. No.1 cylinder is from the flywheel side. k The fuel injection timing is adjusted (FIC) by aligning the timing marks of the gear train. Do not adjust the injection timing using the FID method.

(2)Replacing the fuel injection pump on the local. When the pump has become old and worn, replace the pump in the following manner.

(2-1)Direct injection system engine a The fuel injection pump as the service part is the same as that used in the standard engine (without coupling) (see fig. 1)

Procedure i)Remove the current pump from the gear case. Loosen the end nuts to remove the fuel injection pump. (Leave the fuel injection pump coupling and driving gear as a semi-assembly in the gear case.) k Do not separate the fuel injection pump coupling and driving gear. Do not touch the attachent bolts (4 bolts with E marked). ii)Align the fuel injection pump for service with the aligning marks on the gear case and the pump to install on the gear case (See figure 7). iii)Attach the fuel injection pump coupling and driving gear semi-assembly to the pump.

3 Tightening torque (apply lub. oil): 63.8 ± 5 Nm {6.5 ± 0.5 kgm} Replacing the fuel injection pump is completed. Check the fuel injection timing with the FID method.

(2-2)Swirl pre-combustion system engine

•Replacing only the fuel injection pump

As with the standard engine, injection timing adjusting shims (1) are inserted between the gear case and the fuel injection pump for adjustment. Check the injection timing with the FID method.

Procedure i)Insert the standard shim (0.8 mm), and check the injection timing with the FID method. a The standard shim thickness of the fuel injection pump for EPA use is 0.8 mm for all models. k Do not separate the fuel injection pump coupling and driving gear. ii)If the fuel injection timing is out of specified adjust by changing the thickness of the shims.

•Greater shim thickness: injection timing is delayed

•Lesser shim thickness: injection timing is fast

•Replacing the fuel injection pump cam shaft

Procedure i)Remove the cam shaft, coupling, drive gear and bearing for EPA. ii)Assemble the fuel injection pump cam shaft assembly (cam shaft, drive gear, bearing) for the current production engine and adjust the injection timing with the shims and check the injection timing with the FID method.

(2-3)Swirl pre-combustion system (2D68E-N, 3D68E-N, 3D74E-N only)

Replace with the fuel injection pump assembly for EPA.

Procedure i)Replace the injection timing adjusting shims for the fuel injection pump. Remove the adjusting shims for the failured fuel injection pump and measure its thickness. Replace with the new shims of the same thickness as measured ones. a The fuel injection pump shim thickness for EPA use differs for each fuel injection pump. ii)Check the injection timing with FID method.

If the fuel injection timing is out of specified adjust by changing the thickness of the shims.

•Greater shim thickness: injection timing is delayed

•Lesser shim thickness: injection timing is fast