Troubleshooting; When It Is Difficult To Start The Engine; When Output Is Insufficient; When Engine Suddenly Stops - Rayco Super Jr RG27 Operator, Service, Maintenance Manual

RG27/35/37 Operation • Service • Maintenance
Service

Troubleshooting

Engine
Use the following information to determine the source and
solution to problems you may encounter related to the engine.
This information can also be found in the Kubota Engine
Operator's Manual that shipped with this machine.

When it is difficult to start the engine

Cause
Fuel is thick and ►Check the fuel tank and fuel filter. Remove
doesn't flow water, dirt, and other impurities.
►As all fuel will be filtered by the filter, if there
should be any water or other foreign matters
on the filter, clean the filter with kerosene.
Air or water ►If air is in the fuel filter or injection lines, the
mixed in the fuel pump will not work properly. To maintain
fuel system proper fuel injection pressure, check carefully
for loosened fuel line couplings, loose cap
nut, etc.
►Loosen joint bolt stop fuel filter and air vent
screws of fuel injection pump to eliminate all
the air in the fuel system.
Thick carbon ►This is caused when water or dirt is mixed
deposits on in the fuel. Clean the nozzle injection place
orifice of injec- being careful not to damage the orifice.
tion nozzle ►Check to see if the nozzle is working prop-
erly or not. If not, install a new nozzle.
Valve clearance ►Adjust the valve clearance to 0.145 to 0.185
is wrong mm (0.0057 to 0.0072 in.) when the engine
is cold
Leaking valves ►Grind valves.
Fuel injection ►Adjust injection timing
timing is wrong The injection timing 0.3 rad (18°) before top
dead center.
Engine oil ►Change grade of oil according to the
become thick weather (temperature)
in cold weather
and engine
cranks slow
Low Compres- ►Bad valve or excessive wear of rings, pis-
sion tons, and liners cause insufficient compres-
sion. Replace with new parts.
Battery is ►Charge battery.
discharged and ►In winter, always remove battery from the
the engine will machine, charge fully and keep indoors.
not crank Reinstall in machine at times of use.
48
Countermeasures

When output is insufficient

Cause
Carbon stuck ►Clean orifices and needle valve being very
around orifice of careful not to damage the nozzle orifice..
nozzle place ►Check nozzle to ensure that It is good. If
not, replace the nozzle..
Compression is ►Bad valve and excessive wear of rings,
insufficient. pistons, and liners cause insufficient com-
Leaking valves pression. Replace with new parts..
►Grind valves..
Fuel is insuf- ►Check fuel system..
ficient
Overheating of ►Check lubricating oil system.
moving parts ►Check to see if lubricating oil filter is work-
ing properly.
►Filter element deposited with impurities
would cause poor lubrication. Change
element.
►Check that the clearance of bearings are
within factory specs.
►Check injection timing.
Valve clearance ►Adjust the valve clearance to 0.145 to
is wrong 0.185 mm (0.0057 to 0.0072 in.) when the
engine is cold
Air cleaner is ►Clean the element every 100 hours of
dirty operation.
Fuel injection ►Adjust to proper pressure:
pressure is 13.7 Mpa (140kgf/cm2, 1991 psi)
wrong
Injection pump ►Do not use poor quality fuel as it will cause
wear wear of the pump. Only use No.2-D diesel
fuel.
►Check the fuel injection pump element
and delivery valve assembly and replace as
necessary.

When engine suddenly stops

Cause
Lack of fuel ►Check the fuel tank and refill with fuel, if
necessary.
►Also check the fuel system for air or leaks.
Bad nozzle ►If necessary, replace with a new nozzle.
Moving parts ►Check amount of engine oil with oil level
are overheated gauge.
due to shortage ►Check lubricating oil system.
of lubrication ►At every 2 times of oil change, the oil filter
oil or improper cartridge should be replaced.
lubrication ►Check to see if the engine bearing clear-
ances are within factory specs..
When color of exhaust is especially bad
Cause
Fuel governing ►Contact dealer for repairs.
device bad
Fuel is ►Select good quality fuel.
extremely poor Use No.2-D diesel fuel only..
quality
Nozzle is bad ►If necessary, replace with a new nozzle.
Combustion is ►Cause is poor atomization, improper
incomplete injection timing, etc. Because of trouble in
injection system or in poor valve adjustment
or compression leakage, poor compression,
etc. Check for cause..
Countermeasures
Countermeasures
Countermeasures