Kubota D722-E4, Operator'S Manual

Page: 34 / 42

22 TROUBLESHOOTING
EN
GLISH
TROUBLESHOOTING
If the engine does not function properly, use the following chart to identify and correct the cause.
B
When it is difficult to start the engine
B
When output is insufficient
B
When engine suddenly stops
B
When color of exhaust is especially bad
B When engine must be stopped immediately
Cause Countermeasures
Fuel is thick and
doesn't flow.
*
*
*
Check the fuel tank and fuel filter.
Remove water, dirt and other
impurities.
As all fuel will be filtered by the filter, if
there should be water or other foreign
matters on the filter, clean the filter
with kerosene.
Air or water mixed
in fuel system
*
*
*
If air is in the fuel filter or injection
lines, the fuel pump will not work
properly.
To attain proper fuel injection
pressure, check carefully for loosened
fuel line coupling, loose cap nut, etc.
Loosen air vent screws stop fuel filter
and fuel injection pump to eliminate all
the air in the fuel system.
Engine oil becomes
thick in cold
weather and engine
cranks slow.
*
Change grade of oil according to the
weather (temperature.)
Battery is
discharged and the
engine will not
crank.
*
* Charge battery.
In winter, always remove battery from
machine, charge fully and keep
indoors. Install in machine at time of
use.
Cause Countermeasures
Fuel is insufficient. * Check fuel system.
Overheating of
moving parts
*
*
*
Check lubricating oil system.
Check to see if lubricating oil filter is
working properly.
Filter element deposited with
impurities would cause poor
lubrication. Change element.
Air cleaner is dirty
* Clean the element every 100 hours of
operation.
Injection pump
wear
* Do not use poor quality fuel as it will
cause wear of the pump. Only use No.
2-D diesel fuel. (See "FUEL" in
"PERIODIC SERVICE" section.)
Cause Countermeasures
Lack of fuel
*
*
Check the fuel tank and refill the fuel, if
necessary.
Also check the fuel system for air or
leaks.
Bad nozzle
* If necessary, replace with a new
nozzle.
Moving parts are
overheated due to
shortage of
lubrication oil or
improper
lubrication. *
*
*
Check amount of engine oil with oil
level gauge.
Check lubricating oil system.
At every 2 times of oil change, oil filter
cartridge should be replaced.
Cause Countermeasures
Fuel is of extremely
poor quality. * Select good quality fuel.
Use No. 2-D diesel fuel only.
Nozzle is bad. * If necessary, replace with new nozzle.
Cause Countermeasures
Color of exhaust
suddenly turns
dark.
* Check the fuel injection system,
especially the fuel injection nozzle.
Bearing parts are
overheated.
* Check the lubricating system.
Oil lamp lights up
during operation.
*
*
*
*
Check the lubricating system.
Check the function of the relieve valve
in the lubricating system.
Check pressure switch.
Check filter base gasket.
A If the cause of trouble can not be found, contact your KUBOTA dealer.
E.book Page 22 Wednesday, October 7, 2020 7:17 PM