Sierra MP28870 Emergency Cut-Off Switch, White, Replaces OMC 585134

The Sierra MP28870 is an emergency cut-off switch built to kill ignition power the instant the safety lanyard is pulled free. The circuit stays closed while the lanyard is in place and opens the moment it is removed, cutting the engine so a boat cannot run away from an operator who has left the helm. It is designed for use with conventional or magneto ignitions and mounts through a panel up to 1/4 inch thick, with screw terminals for a straightforward wiring connection. The housing is brass for corrosion resistance in a marine environment, finished in white, and the switch is rated IP54 to help seal out moisture and spray around the panel opening. It operates manually as a 2-way, 2-position break-type switch, and its compact 0.39 x 0.39 x 0.39 inch profile keeps the panel footprint small. The design also makes re-connection easier after the lanyard is reattached. This switch is intended to replace OMC 585134, and the matching replacement lanyard is the Sierra MP28900, which can be ordered separately when the original lanyard wears out or is lost.

Specifications

• Brand: Sierra
• Manufacturer Part Number: MP28870
• Switch Type: Cut Switch
• Color: White
• Material: Brass
• Contact Type: Break
• Circuit Type: 2-way
• Number of Positions: 2
• Connector Type: Screw Terminals
• Mounting Type: Panel Mount
• Operation Mode: Manual
• Panel Thickness: Up to 1/4 inch
• International Protection Rating: IP54
• Dimensions: 0.39 x 0.39 x 0.39 inches
• Weight: 0.07 pounds
• UPC: 808282367169
• Replacement Lanyard: MP28900

Fitment

Designed for use with conventional or magneto ignition systems on panels up to 1/4 inch thick.

Replaces (OEM)

• OMC 585134

Frequently Asked Questions

What does the Sierra MP28870 emergency cut-off switch do? The Sierra MP28870 keeps the ignition circuit closed only while its lanyard is attached; pulling the lanyard opens the circuit and kills engine power, which is the basic safety function of an emergency cut-off switch.

Is the MP28870 compatible with my ignition system? Yes, the Sierra MP28870 is built for use with either conventional or magneto ignition systems, so it covers both common setups found on boats needing this type of cut-off switch.

Does the MP28870 replace OMC 585134? Yes, the Sierra MP28870 is a direct replacement for OMC part number 585134.

What are the dimensions of the MP28870 switch? The Sierra MP28870 measures 0.39 x 0.39 x 0.39 inches, a compact size meant to fit through a small panel cutout.

How thick a panel can the MP28870 be mounted in? This switch is rated for panel mounting on thicknesses up to 1/4 inch.

What is the MP28870 switch made of? The MP28870 has a brass housing, chosen for its corrosion resistance in marine environments, finished in white.

How much does the MP28870 weigh? The Sierra MP28870 emergency cut-off switch weighs 0.07 pounds.

Is the MP28870 sealed against moisture? Yes, it carries an IP54 protection rating, which helps seal out moisture and spray around the switch and panel opening.

What replacement lanyard works with the MP28870? The Sierra MP28900 is the replacement lanyard designed for use with the MP28870 emergency cut-off switch.

Is the MP28870 a manual switch, and how many positions does it have? The MP28870 is a manual, 2-way switch with 2 positions and a break-type contact, meaning the circuit opens when the lanyard is removed.

Does removing the lanyard immediately cut power on the MP28870? Yes, the circuit is closed only while the lanyard is in place on the MP28870; once the lanyard comes off, the circuit opens and power is cut.

What terminals does the MP28870 use for wiring? The Sierra MP28870 uses screw terminals for its electrical connections, making it straightforward to wire into an existing ignition circuit.