HEMRUNK MP41000 marine push-to-choke magneto ignition switch — 7/8" mount, includes 2 keys

The HEMRUNK MP41000 is a marine-grade push-to-choke magneto ignition switch with two keys, compatible with many Sierra and Mercury outboard engines.

This compact ignition switch replaces factory units and provides Off–Run–Start operation, a built-in push-to-choke function and six electrical terminals to integrate into common marine wiring. Designed to fit a 7/8" mounting hole and accommodate a 5/8" panel thickness, the MP41000 is a direct-replacement option referenced by Sierra and Mercury part numbers.

What engines and part numbers work with this switch?

The MP41000 is compatible with a wide range of Sierra and Mercury magneto ignition systems. It is listed under several equivalent part numbers used by OEM and aftermarket suppliers.

• Fits Sierra MP41000 and MP52000 reference numbers.
• Interchanges with Mercury numbers such as 87-88107, 87-17393 and related variants.
• Also cross-referenced to SEA-Dog 420381-1 for some installations.
• Good option for older outboards where these part numbers are specified.

How does the push-to-choke feature simplify starting?

The integrated push-to-choke button replaces a separate choke lever or throttle-mounted switch, making cold starts straightforward. One control on the dash handles choke engagement while keeping the ignition accessible with included keys.

• Push-to-choke activates enrichment without an added throttle switch.
• Simplifies dash layout and reduces wiring points.
• Works with magneto ignition circuits for reliable starting.
• Included keys lock the ignition to prevent unauthorized starts.

What are the physical and electrical installation details?

This switch is intended for panel-mount installation and connects via six terminals, covering typical Off, Run and Start circuits. Confirm panel hole size and terminal layout before ordering to ensure proper fit and wiring compatibility.

• Mounting hole required: 7/8" diameter.
• Panel accommodation up to 5/8" thick for secure mounting.
• Six electrical terminals support standard magneto wiring and starter circuit.
• Three-position operation: Off, Run, Start for common outboard controls.

What comes in the box and what should I expect on the boat?

Each purchase includes the ignition switch body and two cut keys so you can install and secure the system right away. The unit is pre-wired with terminals ready for spade connectors or soldered connections, depending on your setup.

• Package includes one MP41000 ignition switch plus two keys.
• Ready for standard marine electrical connections at the terminals.
• Compact housing designed for flush panel mounting on instrument clusters.
• Use with compatible Sierra/Mercury magneto engines for best results.

Who is this for? The HEMRUNK MP41000 is suited for boat owners, mechanics and marine hobbyists replacing an aging or failed ignition switch on compatible Sierra or Mercury outboards. It’s especially useful when you want a simple dash setup with built-in choke function and secure keyed ignition—ideal for maintenance, restoration projects, or upgrading older boats where the listed part numbers match your engine's requirements.