Komatsu 830E Shop Manual page 659

Troubleshooting
It is important to understand the LED signal for the
pumping unit. It is used primarily to verify that the sys-
tem is maintaining the oil level at the level of the open
end of the withdrawal tube in the engine oil pan. The
signal is also a valuable tool in troubleshooting the sys-
tem.
When the signal is "STEADY" (NOT FLASHING), pump
1 is running and oil is being withdrawn from the engine
and being transferred to the reserve tank.
When the signal is "FLASHING", pump 1 is drawing air
from the suction tube which triggers operation of the
pump 2 to operate and transfer oil back to the engine
from the tank (the flashing is actually the pulses of
pump 2). When the oil is at the correct level in the
engine, air and oil are alternatively entering the suction
tube, with pump 1 commanding operation of pump 2
with each portion of air that comes through the line.
This is a complete test for proper operation of the
pumping unit. This operation can be accomplished
without running the engine by jumping the oil pressure
switch that activates the system.
1. If the signal light is "STEADY", pump 1 should be
pumping oil. Verify by loosening the hose at
pump 1 outlet to verify that oil is coming through
(pump 1 is marked by a groove on its outlet).
2. Loosen the hose at the inlet of pump 1 to admit
air. Pump 2 should then run and the signal
should be flashing.
pump 2 by loosening the hose at its outlet to see
that oil is coming through.
3. Re-tighten the inlet hose on pump 1. The pump
should again receive oil and the flashing should
stop.
M31001
Verify proper pumping of
Reserve Engine Oil System
NOTE: There is a condition that would show a level
higher than the controlled point. If both the engine and
reserve tank are overfilled, there is no room in the tank
to draw the oil level down in the engine. In this case,
the LED signal would never start "FLASHING" because
pump 1 is never receiving air. It will continue to pump
oil from the engine to the tank, but because the tank is
full, the oil will be routed back to the engine via the air
relief valve on top of the tank.
There are two explanations for an overfilled tank and
engine:
•
When the tank is filled to "FULL" and the engine
is overfilled.
•
When oil is added directly to the engine between
oil changes. The system transfers the oil to the
reserve tank until it can not recieve any more
and the engine remains overfilled. It is, there-
fore, important that oil should be added only to
the reserve tank between oil changes; except,
of course, if the engine is extremely low.
M31-5