Level Gauges / Level Maintainers | LM500-TF/LM302

Sight GlassYESYES
Low Level SwitchYESYES
High Level SwitchNOYES
Level MaintainerYESYES
Pipe Bracket Kit1500051815000371
Flange Mount1500051915000370
Oil CompatibleYESYES
Diesel/ CoolantNONO




Lube Level Maintainer – LM500TF

The LM500 maintains oil level on any size engine. It
also supports installations that require a three-wire,
snap-action switch. The form C (three-wire) contact
allows a controller/annunciator to be wired as a closed

loop system, resulting in a reliable fault-sensitive circuit.
Refer to LM500 Series Flow Rate Chart for application
The FW Murphy LM500-TF Oil Level Maintainer
includes a test feature that confirms both the float and
switch are operating correctly with a single press of the
test button. The LM500 series maintains the crankcase
oil level of an engine, pump or compressor. Adjusted to
the correct running oil level, it will replenish oil as it is
used. The low-level switch will alarm and/or shut-down
the equipment, if supply oil is lost and the equipment
continues to use oil.
As crankcase oil level drops, the LM500 float also
drops and opens the thumb valve. This allows oil to
flow from the supply tank through the LM500 and into
the crankcase. When proper level is achieved in the
crankcase, the LM500 float rises causing the thumb
valve to close off further oil flow.
The simple and unique thumb valve is non-clogging
and provides a positive, leak-free seal.
If the clean oil supply is depleted and oil level
continues to fall, the low-level switch will operate an
alarm or equipment shutdown.


Level Maintainer – LM302

The LM300 Series Level Maintainer automatically adds
oil to the crankcase as needed to keep the lube level
normal. Most models have built-in switches that will
alarm and/or shut down the equipment if the makeup
supply is depleted and engine oil level falls or if overfill
conditions exist. The LM300 can be used in engines,
compressors, pumps and coolers.