Komatsu 830E-AC Shop Manual page 895

TROUBLESHOOTING
It is important to understand the LED signal for the
pumping unit. It is used primarily to verify that the
system 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 system.
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running and oil is being withdrawn from the engine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 suc-
tion 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 pres-
sure 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. Verify proper pumping of
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.
M31004
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 receive any more and
the engine remains overfilled. It is, therefore,
important that oil should be added only to the
reserve tank between oil changes; except, of
course, if the engine is extremely low.
Circuit Fuse
The Reserve System is protected by a 15 amp fuse
(Fuse Block 2, position 10) located in the auxiliary
control cabinet.
For circuit information, refer to the system schematic
in the back of the shop manual.
Reserve Engine Oil System M31-7