Komatsu PC130-7, Shop Manual, Page: 322 / 342

20-606
PC130-7
TROUBLESHOOTING
Check items
Questions
Troubleshooting
Yes
No
Clogged air
cleaner
eleme
nt
Defecti
ve contact of valve, valve se
at
W
orn pist
on
ring, cylinder
Clogg
ed fuel filter, st
rainer
Clogg
ed fee
d pump gauze filter
Elect
rical intake
air he
ate
r
When compression pressure is measured, it is found to be low
When air cleaner element is inspected directly, it is found to be clogged
When fuel filter, strainer are inspected directly, they are found to be clogged
When feed pump strainer is inspected directly, it is found to be clogged
Heater mount does not become warm
Is voltage 26–30V between alternator terminal B and terminal E
with engine at low idling?
Either specific gravity of electrolyte or voltage of battery is low
Speed does not change when operation of certain cylinders is stopped
When control rack is pushed, it is found to be heavy or does not return
(check after removing fuel injection pump)
When fuel tank cap is inspected directly, it is found to be clogged
Use a test stand when adjusting.
Replace Correct Clean Clean Clean Replace
Remedy
Confirm recent repair history
Indicator lamp does not light up
Engine oil must be added more frequently
Replacement of filters has not been carried out according to operation Manual
Non-specified fuel has being used
Dust indicator lamp is red
Battery charge lamp is ON
Starting motor cranks engine slowly
When exhaust manifold is touched immediately after starting engine,
temperature of some cylinders is low
Engine does not pick up smoothly, and combustion is irregular
Blow-by gas is excessive
Timing lock on fuel injection pump does not match
Mud is stuck to fuel tank cap
When engine is cranked with starting motor,
1) Little fuel comes out even when injection pump piping sleeve nut is loosened
2) Little fuel comes out even when fuel filter air bleed plug is loosened
Leakage from fuel piping
There is hunting from engine (rotation is irregular)
Operated for long period
Gradually became worse
Starts when warm
Degree of use of machine
Ease of starting
Causes
S-1 Starting performance is poor
(Starting always takes time)
General causes why exhaust smoke comes out but engine takes time to start
•
Defective electrical system
• Insufficient supply of fuel
• Insufficient intake of air
• Improper selection of fuel
(At ambient temperature of –10°C or below,
ASTM D975 No. 2 diesel fuel is used)
a
Battery charging rate and gravity
• The specific gravity should exceed the value for the charging
rate of 70% in the above table.
• In cold areas the specific gravity must exceed the value for the
charging rate of 75% in the above table.
Charging rate
Ambient
temperature
100 % 90 % 80 % 75 % 70 %
20°C 1.28 1.26 1.24 1.23 1.22
0°C 1.29 1.27 1.25 1.24 1.23
–0°C 1.30 1.28 1.26 1.25 1.24
S-1
(1)