Installation of Lube Level Maintainer

Before Installation

Please read the following instructions and warnings before installation. Visually inspect the product for any damage that may have occurred during shipping.

• It is your responsibility to ensure that qualified mechanical and electrical technicians install this product.
• Disconnect all electrical power to the machine.
• Make sure the machine cannot operate during installation.
• Follow all safety warnings of the machine manufacturer.
• Read and follow all installation instructions.
• Please contact FW Murphy Production Controls immediately if you have any questions.

Product Overview

The FW Murphy LM500 model maintains the crankcase oil level of an engine, pump or compressor. Adjusted to the correct running oil level, the LM500 will replenish oil as it is used. The low level switch will alarm and/or shut down the equipment if the supply oil is lost and the equipment continues to use oil. The LM500-TF model includes a test feature that confirms both the float and switch are operating correctly with a single press of the test button.

Range of the Snap-Switch

This illustration shows the LM500 dial and the operating range of the switch. If level is within the designated zones, the switch will activate.

The switch activates approximately 1/4 in. (6 mm) from the bottom of the low zone. If the level continues to drop into the low-low zone, a shutdown will occur.

Diagram Description: A diagram shows the LM500 unit with dimensions. It indicates approximate engine running oil levels in feet of head: 4', 11', and 25'. A 'Low Zone Shutdown' is indicated at 0.31 inches (7.9 mm). A note explains that color zones on the dial face show approximate normal operating zones, but actual conditions may vary.

Test Feature: The form C (3-wire) contact allows a controller/annunciator to be wired as a closed loop system, resulting in a reliable fault-sensitive circuit.

NOTE: Holding test button for a prolonged period of time could cause crank case to overfill.

Diagram Description: A graph titled 'LM500 Series Flow Rates' shows temperature in Fahrenheit on the x-axis and flow rate on the y-axis. The line indicates that flow rate increases with temperature. A note states that the flow rates are based on SAE 40 motor oil at 2 ft. head pressure, and friction losses due to piping are not considered.

Operation

As the equipment uses oil, the float falls, providing immediate level compensation. At the FULL position, the float holds the valve closed. If the clean oil supply is depleted and oil level continues to fall, the low level switch will operate an alarm or equipment shutdown.

NOTE: Holding test button for a prolonged period of time could cause crank case to overfill.

Diagram Description: A simplified diagram illustrates the float action within the LM500 case. The float moves from LOW to FULL, operating a thumb valve. The low level switch is shown with connections for COM (white), N.O. (black), and N.C. (red).

Dimensions, Mounting Brackets (Optional)

Diagram Description: Two mounting bracket types are shown with detailed dimensions:

• Pipe Mount Bracket: Shows dimensions for mounting holes and the bracket itself. Includes a note about 4x 1/4-20 UNC fasteners.
• Universal Mount Bracket: Shows dimensions for the bracket and its mounting slots. Includes notes about 3/8 Bolt Slots and 1/4 Bolt Slots.

Dimensions, LM500 Series

Diagram Description: Front and side views of the LM500 and LM500-TF units are provided with detailed dimensions:

• LM500: Shows overall width, height, and depth, including conduit connection, vent, viewing lens, and oil inlet/outlet ports.
• LM500-TF: Similar to LM500, but also indicates the location of the Test Button.

Typical Installation

Attach the mounting bracket to the backside of the LM500. If using the Universal bracket, this may be done now or after the bracket is attached to the base or the oil pan.

Diagram Description: An illustration shows how to attach a mounting bracket to the LM500 unit, indicating 4x 1/4-20 UNC fasteners.

Supplied in bracket kit: Mounting bolts 1/4-20 UNC x 3/4 long and washers.

• The Pipe bracket uses 4 screws with a lock washer on each.
• The Universal bracket uses 4 screws with a lock washer and flat washer on each.

Follow instructions for Pipe Bracket Kit (15000518) or Universal Flange kit (15000519). See LM500 Series Kits.

IMPORTANT: Mount the LM500 as close as possible to the crankcase.

Pipe Bracket Mount (PM) (P/N 15000518)

1. Mount a nominal 1/2 inch (13 mm) diameter pipe to the base of the skid or fixture.
2. If not already done, install the pipe bracket to the LM500 using the supplied fasteners, four 1/4-20 UNC x 3/4 inch bolts with lock washers on each.
3. Slip the LM500 onto the pipe and install the two adjustment bolts (nuts threaded close to bolt head), 1/4-20 UNC x 1-1/2 inch bolt.
   • DO NOT tighten the adjustment bolts too tight, as you will need to adjust the LM500 later in the installation process.
   • Refer to Connect Fittings and Hoses for more information regarding height adjustment of the LM500 in alignment with the oil level in the crankcase.

Diagram Description: Illustrations show the steps for attaching the pipe bracket and adjusting the LM500 unit onto a pipe.

Universal Flange Mount (UB) (P/N 15000519)

The Universal Flange bracket has two mounting methods: base mounting or oil pan mounting.

Base Mounting

1. Install the universal bracket to the base as shown using a 5/16 inch diameter bolt and lock washer, customer supplied.
2. If not already done, mount the LM500 to the universal bracket using the supplied fasteners, four 1/4-20 UNC x 3/4 inch bolts with lock and flat washers.
   • DO NOT tighten the bolts too tight, as you will need to adjust the LM500 later in the installation process.
   • Refer to Connect Fittings and Hoses, for more information regarding height adjustment of the LM500 in alignment with the oil level in the crankcase.

Diagram Description: Illustrations show the universal bracket mounted to a base and the LM500 unit attached to the bracket, with 4-Bolts and 8-Washers indicated.

Crankcase (Oil Pan) Mounting

1. Install the universal bracket to the crankcase using an existing crankcase bolt, washer and nut. Crankcase bolt diameter must be no larger than 7/16 inch (11 mm).

2. NOTE: Check clearance between crankcase and mounting bracket before installing the mounting bracket. If space between the crankcase and mounting bracket is narrow, attach LM500 to mounting bracket prior to installation on crankcase.

3. If not already done, mount the LM500 to the universal bracket using the supplied fasteners, four 1/4-20 UNC x 3/4 inch bolts with lock and flat washers.
   • DO NOT tighten the bolts too tight, as you will need to adjust the LM500 later in the installation process.
   • Refer to Connect Fittings and Hoses, for more information regarding height adjustment of the LM500 in alignment with the oil level in the crankcase.

Diagram Description: Illustrations show the universal bracket being mounted to the crankcase, with a note to check clearance, and the LM500 unit attached to the bracket, with 4-Bolts and 8-Washers indicated.

Connect Fittings and Hoses

The following instructions start after LM500 is mounted, using Hose Kit (15000355) and Fitting Kit (15000943).

IMPORTANT: If connecting to the drain plug on the crankcase, we recommend adding a T-fitting to allow draining of the oil for service.

IMPORTANT: Apply a sealant such as Teflon® to all threaded connections.

Perform the Operation Test after the unit is installed and wired appropriately.

1. Ensure the crankcase oil level is below the connections needed for this procedure.
2. Start the engine or power up the monitor.
3. Using the barb fittings as needed, attach the 1 inch (25 mm) diameter flexible oil hose to the crankcase and to one of the (3) oil outlet locations on the LM500. Secure with hose clamps.
   • The hose must slope slightly downward from the LM500 and without any droops or low spots.
   • If crankcase drain plug is used, we recommend installing a T-fitting at the crankcase to assist with routine oil changes.
4. Apply Teflon to threads of the 3/4-14 NPT pipe plug fitting. Install pipe plug fittings to the remaining (2) oil outlets. Plugs supplied in LM500's shipping box.
5. For vented crankcase: You may use the plastic vent plug that came installed in the LM500 or install the vent tube (candy cane).
   • To install the vent tube, remove the plastic vent plug. Install and tighten the compression fitting connector with the vent tube.
6. For sealed systems: Remove the plastic vent plug. Use the barb fittings to install the 1/2 inch (13 mm) I.D. x 3 ft. (914 mm) hose to the vent connection on the LM500 and to the vent connection on the crankcase. Cut hose as needed and secure with hose clamps.
   • The vent connection on the crankcase must be well above the regulated oil level.
   • The hose must be clear of obstructions, valleys or dips that could create liquid traps or gas/air pockets. The connections should be as straight as possible.
7. Before continuing, verify that all hose clamps are tight.
8. Fill the crankcase to the proper oil level.
9. With the engine running and warm, loosen the mounting bracket adjustment bolts and adjust the LM500 so that the oil level in the viewing lens aligns with the middle of the green bar on the dial.
10. Holding the LM500 in alignment, tighten the adjustment bolts on the mounting bracket.

Diagram Description: Illustrations show vent options for vented and sealed systems, including the use of a plastic vent plug or vent tube, and the connection of a vent hose. A 'Sealed System and Alignment Illustration' shows the LM500 unit connected to the crankcase with a vent hose and oil hose, indicating the running engine oil level relative to the viewing lens and green bar.

Connect LM500 to Oil Supply Tank

Perform the Operation Test after the unit is installed and wired appropriately.

1. Remove the plug from the oil inlet connection. Be sure the removable screen inside the connection is clear of debris. Install the oil inlet connection.
2. Connect a 1/2 inch I.D. (13 mm) or larger hose to the oil inlet fitting on the LM500 and to the shut-off valve on the oil supply tank.
   • Recommended minimum height above the LM500 is 2 feet. (0.6 m); maximum 25 feet (7.7 m).
   • The hose must maintain a downward slope and not have low spots or droops.
   • Maximum head pressure rating is 9.50 psi or 25-foot oil (head pressure).
3. Before filling the supply tank with oil, be sure the tank is clean and dry and the shut-off valve is closed. Also, be sure all hoses and clamps are tight. Fill the tank with CLEAN oil.

4. After oil supply tank is full, open the shut-off valve.
5. Make the proper electrical connections for the application.

Diagram Description: Two installation diagrams illustrate connecting the LM500 to an oil supply tank:

• LM500 Typical Installation Diagram With Supply Tank: Shows a general setup with a supply tank, shut-off valve, LM500 unit, and electrical connections. Notes indicate requirements for vented and sealed crankcases.
• Typical Pipe Mount Installation: Shows the oil outlet hose connected to the bottom outlet, with side outlets plugged.
• Typical Universal Mount Installation: Similar to the pipe mount, showing the oil outlet hose connected to the bottom outlet, with side outlets plugged.

LM500 Series Kits

Pipe Bracket Kit (P/N 15000518)

Universal Bracket Kit (P/N 15000519)

Bubble Lens Kit (P/N 15000532)

Fittings Kit (P/N 15000943)

Hose Kit (P/N 15000355)

Vent Fittings Kit (P/N 15000954)

Specifications

• 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
• Snap-switch: SPDT rating 10 A, 125 VAC; 0.5 A, 125 VDC; 10 A, 30 VDC
• Wire leads: 18 AWG x 14 in. +/- 2 in. (355 mm) length
• Conduit 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 Differential: 2 in. (51 mm) between running and stopped
• Maximum Ambient Temperature: 250° F (121° C)
• Float: 304 Stainless Steel
• Flow Rates: Refer to Flow Rate Chart

Company Information

In order to consistently bring you the highest quality, full-featured products, FW Murphy Production Controls reserves the right to change specifications and designs at any time. FW Murphy product names and the FW Murphy logo are proprietary trademarks. This document, including textual matter and illustrations, is copyright protected with all rights reserved. © 2022 FW Murphy. A copy of our typical warranty may be viewed or printed by going to www.fwmurphy.com/warranty.

FW Murphy Production Controls

Sales, Services & Accounting
4646 S. Harvard Ave.
Tulsa, OK 74135

Manufacturing
2151 Randon Dyer Road
Rosenberg, TX 77471
5757 Farinon Drive
San Antonio, TX 78249

Domestic Sales & Support

FW Murphy Products
Phone: 918 957 1000
Email: INFO@FWMURPHY.COM
WWW.FWMURPHY.COM

FW Murphy Control Systems & Services
Phone: 281 633 4500
Email: CSS-SOLUTIONS@FWMURPHY.COM

International Sales & Support

China
Phone: +86 57187886060
Email: INTERNATIONAL@FWMURPHY.COM

Latin America & Caribbean
Phone: +1918 770 8775
Email: INTERNATIONAL@FWMURPHY.COM

South Korea
Phone: +82 70 7951 4100
Email: INTERNATIONAL@FWMURPHY.COM

ISO 9001 Quality Management (San Antonio, TX - USA; Rosenberg, TX - USA; China)

IATF 16949 Automotive Quality Management (China)