15700835 – Murphy Lube Level Maintainer – LM500


Murphy Level Maintainer


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 closedloop system, resulting in a reliable fault-sensitive circuit. Refer to LM500 Series Flow Rate Chart for application data.

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.

Estimate available in 28 working days from Italy to Italy

This product may vary on delivery times, as factories do not guarantee production due to lack of raw materials.

Availability: Available on backorder SKU: 15700835 Categories: , Tags: ,



  • Crankcase Balance Vent Connection: 1/2 NPTF (top)
  • Inlet Connection: 1/2 NPTF removable screen (side)
  • Outlet Connection:
    • 2 x 3/4 NPTF (side)
    • 1 x 3/4 NPTF (bottom)
  • Thumb-Valve Material: Viton
  • Span-switch: SPDT rating 10 A, 125 VAC; 0.5 A, 125 VDC; 10A, 30 VDC
  • Wire leads: 18 AWG x 14 in. +- 2 in. (355 mm) length
  • Condution Connection: 1/2 inch conduit (female, top)
  • Case: Die cast aluminum
  • Lens: Clear Frog Eye non-staining, high-impact, high
  • Temperature polycarbonate; UV and heat stabilized
  • Dial: High visibility white background with solid green band for normal level indication
  • Maximum Inlet Pressure: 9.50 psi/25 ft. oil (head pressure)
  • Maximum Case Pressure: 15 psi (103 kPa)
  • Maximum Differential: 2 in. (51 mm) between running and stopped
  • Maximum Ambient Temperature: 250°F (121° C)
  • Float: 304 Stainless Steel
  • Flow Rates: Refer to LM500 Series Flow Rates chart for application data
  • Dimension: Overall 6-9/16 in. (H) x 6-3/16 in. (W) x 3-1/2 in. (D)
  • LM500/LM500-TF Shipping Dimensions: 9.5 (W) x 7.5 (D) x 11 in (H) (241.3 (W) x 190 (D) x 279.4 mm (H)
  • LM/LM500-TF Shipping Weight: 3 lbs 13.44 oz (1.74 kg)



LM500 Series Flow Rates


Mounting Brackets with Hardware

In addition to the direct mounting option, Enovation Controls offers two mounting brackets for the LM500. The pipe bracket fits a 7/8 in. (22 mm) diameter pipe (see typical installation).TheUniversal Flange Kitallows various mounting methods.

Typical Installations


How to order

In the web-shop is present standard version for remaining below parts are needed a separately quotation.


Part NumberDescriptionNote
15000954Vent Fittings Kitone tubing vent, one 1/4 x 1/2 NPT connector
15000355Hose Kitone – 1/2 in. (13 mm) I.D. x 3 ft. (914 mm) hose
one – 1 in. (25 mm) I.D. x 3 ft. (914 mm) hose
two – 1/2 in. (13 mm) worm gear clamp
two – 1 in. (25 mm) worm gear clamp
two – 1/2 NPT x 1/2 in. (13 mm) barbed fitting
two – 3/4 NPT x 1 in. (25 mm barbed fitting
890808011/2 NPT x 1/2 in. Hose Barbed Fitting
890810013/4 NPT x 1 in. Hose Barbed Fitting
15000518Pipe Bracked Kit
15000519Universal Flange Kit
15000532Bubble Lens Kit
15000943Fittings Kitone tubing vent; one hose barb, 1/2 NPT to 1/2 Hose; one hose barb, 1″ ID hose 3/4 NPT; one connector, 1/4 x 1/2 NPT

Additional information

Weight1,74 kg


15700835, LM500