Rotary Solenoid Model 3319 Instruction Manual

1. Introduction

This instruction manual provides essential information for the proper installation, operation, and maintenance of the Rotary Solenoid Model 3319. This solenoid is designed as a direct replacement for various Murray lawn mower models, ensuring reliable starting performance. Please read this manual thoroughly before installation to ensure safety and optimal functionality.

Compatible Murray Part Numbers:

• 24285
• 424285
• 7701100MA
• 7769224MA
• 94613MA
• 9924285

2. Safety Information

Always prioritize safety when working with electrical components and machinery. Failure to follow these safety guidelines may result in injury or damage to equipment.

• Disconnect Power: Before beginning any installation or maintenance, ensure the lawn mower's battery is disconnected to prevent accidental starting or electrical shock.
• Wear Protective Gear: Use appropriate personal protective equipment, such as safety glasses and gloves.
• Consult Service Manual: Refer to your lawn mower's specific service manual for detailed instructions and safety precautions related to your model.
• Proper Tools: Use only appropriate tools for the task to avoid damage to components.
• Professional Assistance: If you are unsure about any step, seek assistance from a qualified technician.

3. Product Overview

The Rotary Solenoid Model 3319 is an electrical switch that allows a small current from the ignition switch to activate a larger current flow from the battery to the starter motor, initiating engine cranking. It features two large terminals for battery and starter connections and one small terminal for the ignition signal.

Figure 1: Rotary Solenoid Model 3319. This image displays the black solenoid body with two large copper studs at the top and a smaller silver stud at the front, all with nuts and washers for secure connections. The base has two mounting holes.

Key Features:

• Upper Stud Thread: 1/4"
• Lower Stud Thread: 3/16"
• Durable construction for reliable performance.
• Direct replacement for specified Murray models.

4. Installation Instructions

Follow these steps carefully to install the Rotary Solenoid Model 3319:

1. Prepare the Mower: Ensure the lawn mower is turned off, the key is removed, and the parking brake is engaged.
2. Disconnect Battery: Disconnect the negative (-) battery cable first, followed by the positive (+) battery cable. This prevents accidental short circuits.
3. Locate Old Solenoid: Identify the existing solenoid on your lawn mower. It is typically mounted near the battery or starter motor.
4. Disconnect Wires: Carefully disconnect all wires from the old solenoid. Note the position of each wire (e.g., battery positive, starter motor, ignition signal) for correct re-connection. Taking a photograph before disconnecting can be helpful.
5. Remove Old Solenoid: Unbolt and remove the old solenoid from its mounting location.
6. Mount New Solenoid: Position the new Rotary Solenoid Model 3319 in the same location as the old one. Secure it using the appropriate bolts. Avoid overtightening to prevent damage to the mounting base.
7. Connect Wires: Reconnect the wires to the new solenoid.
   • Connect the battery positive cable to one of the large studs (typically the one connected to the battery).
   • Connect the starter motor cable to the other large stud (typically the one connected to the starter).
   • Connect the ignition signal wire to the small terminal.
   Ensure all connections are clean and tight.
8. Reconnect Battery: Reconnect the positive (+) battery cable first, then the negative (-) battery cable.
9. Test Operation: Attempt to start the lawn mower to verify proper installation and functionality.

5. Operating Principles

When the ignition key is turned to the "start" position, a small electrical current flows from the ignition switch to the small terminal on the solenoid. This current energizes an electromagnet inside the solenoid, which then pulls a plunger, closing a set of heavy-duty contacts. These contacts complete the high-current circuit between the battery and the starter motor, allowing the starter to crank the engine. Once the engine starts and the key is released, the electromagnet de-energizes, opening the contacts and cutting power to the starter.

6. Maintenance

Regular maintenance helps ensure the longevity and reliable operation of your solenoid:

• Inspect Connections: Periodically check all electrical connections to the solenoid for tightness and corrosion. Loose or corroded connections can impede current flow and cause starting problems.
• Clean Terminals: If corrosion is present, disconnect the battery and clean the terminals and wire ends with a wire brush or sandpaper.
• Check for Damage: Inspect the solenoid body for any signs of physical damage, cracks, or excessive heat discoloration.
• Environmental Protection: Keep the solenoid free from excessive dirt, moisture, and debris.

7. Troubleshooting

If your lawn mower is experiencing starting issues after solenoid installation, consider the following:

For further assistance, consult a qualified technician or your lawn mower's service manual.

8. Specifications

9. Warranty and Support

For warranty information or technical support regarding your Rotary Solenoid Model 3319, please refer to the documentation provided with your purchase or contact the retailer or manufacturer directly. Keep your proof of purchase for warranty claims.

Manufacturer Contact: Please refer to the official Rotary website or product packaging for the most current contact information.