Installing A Fuel Injection Pump; Adjusting Fuel Injection Timing; Troubleshooting Of Fuel Injection Pump - Yanmar 3JH4E Service Manual

6.1.5 Installing a fuel injection pump

[NOTICE]
• Use a new O-ring on the fuel pump flange and
apply grease.
• Confirm whether the marks of the pump drive
gear and the idle gear is correct.
1) Turn a camshaft so that the key of the pump
camshaft may almost agree in a position of
the key groove of a pump drive gear.
2) Insert a fuel injection pump into the
installation hole of the gear case straight to
prevent the damage of the O-ring. Insert a
fuel pump while confirming whether the key
of a camshaft and the key groove of a drive
gear agree.
3) Assemble a pump drive gear nut and a
washer together temporarily.
4) Turn a fuel injection pump to the position
where the marks of the fuel injection pump
and the gear case agrees.
5) Fasten pump installation nuts (three nuts) on
the fuel injection pump.
6) Tighten the pump installation nut by the
specified standard torque.
Tightening torque of the pump drive gear nut (without
lube oil)
Tightening torque
78-88 (8-9)

6.1.6 Adjusting fuel injection timing

Refer to 2.2.6(1) in chapter 2.
6.1.7 Troubleshooting of fuel injection
pump
Complete repair means not only replacing defective
parts, but finding and eliminating the cause of the
trouble as well. The cause of the trouble may not
necessarily be in the pump itself, but may be in the
engine or the fuel system. If the pump is removed
prematurely, the true cause of the trouble may
never be known. Before removing the pump from
the engine, at least go through the basic check
points given here.
Basic checkpoints
• Check for breaks or oil leaks throughout the fuel
system, from the fuel tank to the nozzle.
• Check the injection timings for all cylinders. Are
they correctly adjusted? Are they too fast or too
slow?
• Check the nozzle spray.
• Check the fuel delivery. Is it in good condition?
Loosen the fuel pipe connection at the injection
pump inlet, and test operate the fuel feed pump.
Nm(kgf•m)
221
6. Fuel Injection equipment