Murphy 117 Magnetic Switch 25700071 - Reliable Engine Shutdown

In this review of the Murphy 117 Magnetic Switch 25700071 the bottom line is simple: this is a reliable, purpose-built magnetic switch for engine and motor shutdown applications aimed at technicians and maintenance teams who need a straightforward alarm or shutdown interface. The reviewer found the unit useful where controlled interruption of ignition or fuel systems is required, and appreciated that it supports both distributor and magneto/CD ignition methods as well as fuel valve tripping. For anyone specifying a compact magnetic switch for industrial engines or electric motors the 117 stands out for clear functionality rather than bells and whistles.

Key Features

• Magnetic switching for engines: Opens the distributor coil circuit on distributor ignition engines to cause a reliable shutdown.
• Compatibility with magneto and CD ignitions: Grounds the ignition output on those systems so it can be used across different ignition types.
• Fuel valve tripping option: Some configurations can trip fuel valves instead of or in addition to grounding ignition, offering flexibility for diesel shutdown by fuel cutoff.
• Tattletale annunciator capability: Can be used with annunciators or alarm systems for alarm-only or alarm-before-shutdown setups to match operational requirements.
• Multiple contact configurations: Available in various circuits and time delays so the switch can match power source and mode of operation needed on site.

Who It's For

The Murphy 117 is best for mechanics, fleet maintenance crews, and industrial electricians who need a rugged magnetic switch to integrate into engine and electric motor control and shutdown systems. It is particularly suitable where the requirement is to interrupt ignition circuits or actuate fuel control valves in a predictable manner.

It is less appropriate for consumer or aesthetic applications where form factor, integrated electronics, or user-facing features matter. Customers needing a full control module with programmable logic or remote telemetry should look elsewhere and pair this switch with complementary control hardware.

Pros & Cons

Pros

• Purpose-built design makes it straightforward to use for engine shutdown on distributor ignitions.
• Supports magneto and CD ignition grounding, increasing compatibility across engine types.
• Available options to trip fuel valves and work with Tattletale annunciators add useful flexibility for diesel and alarm-before-shutdown scenarios.

Cons

• Specification details such as physical dimensions and exact electrical ratings are not provided in the basic description, so installers must confirm compatibility before purchase.

Specifications

Product name	Murphy 117 Magnetic Switch
Part number	25700071
Primary use	Engine and electric motor shutdown / alarm interfaces
Ignition compatibility	Distributor, magneto and CD ignitions
Additional function	Can trip fuel valves or ground ignition output
Alarm integration	Works with Tattletale annunciators and alarm-before-shutdown circuits

Our Verdict

The Murphy 117 Magnetic Switch 25700071 is a dependable component for technicians needing a simple, effective way to interrupt ignition or actuate fuel shutdowns. It offers practical flexibility across ignition types and integrates with annunciators, making it good value as part of an industrial engine control solution for professionals who will verify electrical ratings and fit before installation.

Frequently Asked Questions

Can this switch shut down diesel engines?
Yes; diesel engines can be shut down by tripping fuel valves or closing air supply, and some 117 models can trip fuel valves.

Will it work with both distributor and magneto ignitions?
Yes; on distributor systems it opens the distributor coil circuit, and on magneto or CD systems it grounds the ignition output.

Can it be used with alarm systems?
Yes; the switch is compatible with Tattletale annunciators and supports alarm-only or alarm-before-shutdown configurations.