Testing Fuel Pressure - Komatsu 114E-3 Series Shop Manual

30 Testing and adjusting

Testing fuel pressure

a Testing tools for fuel pressure
Symbol Part No.
799-101-5002 Hydraulic tester
1
790-261-1204 Digital hydraulic tester
6732-81-3170
2
6215-81-9710 O-ring
G
3 799-401-2320 Gauge: 1 MPa {10 kg/cm
4 795-790-6210 M10 computer check fitting
795-790-1500
5
799-201-1201
a Test only the fuel pressure in the negative
pressure circuits from the fuel supply connec-
tor and feed pump and in the low-pressure cir-
cuit from the feed pump through the fuel main
filter and supply pump.
k
Since the pressure in the high-pressure cir-
cuit from the fuel supply pump through the
common rail to the injector is very high, it
cannot be measured.
1. Testing fuel negative pressure circuit pres-
sure (fuel supply connector)
1) Remove fuel pressure pickup plug (1)
from the fuel supply connector.
114E-3 Series
Part name
Adapter
(10 x 1.0 mm o PT1/8)
Fuel vacuum gauge
1
2) Connect M10 computer check fitting G4 to
fuel vacuum gauge G5.
2
}
3) Run the engine at high idle and test the
fuel negative pressure circuit pressure.
a If the fuel negative pressure circuit
q
4) After finishing testing, remove the testing
tools and return the removed parts.
3
2. Testing fuel negative pressure circuit pres-
sure (supply pump)
1) Remove fuel pressure pickup plug (2)
from the supply pump.
pressure is in the following range, it is
normal.
Standard value of fuel negative pres-
sure circuit pressure (fuel supply con-
nector):
Max. 27.1 kPa {Max. 203 mmHg}
Fuel pressure pickup plug:
20 – 22 Nm {2.0 – 2.2 kgm}
SEN00455-01
13