Line locks are devices used in brake systems to temporarily hold pressure, often employed in motorsports and performance applications. This article details the installation process and system requirements based on available documentation. The information provided is intended for individuals with mechanical experience and a thorough understanding of brake system components. It is crucial to follow all safety precautions and manufacturer guidelines during installation and operation.
Understanding Line Lock Systems
A line lock functions as an electrically activated valve installed within a vehicle’s brake line. When activated, it prevents brake fluid from returning from the wheel cylinders or calipers to the master cylinder, effectively holding the brakes applied to that wheel or wheels. This is commonly used for staging in drag racing, preventing vehicle movement while maintaining brake pressure. The documentation specifies that line lock installation kits are designed for vehicles equipped with SAE thread components only and are not compatible with metric brake lines or fittings.
Kit Contents and Component Selection
Installation kits typically include a variety of brass fittings and steel brake lines necessary for integrating the line lock into the existing brake system. The documentation from Spelabautoparts.com lists the following components:
- 3/16" Inverted Female to 1/8" NPT Male Connector
- 1/4" Inverted Male to 3/16" Inverted Female Connector
However, the documentation notes that due to the variety of brake system combinations, additional brake lines or fittings may be required to complete the installation in some applications. Careful assessment of the existing brake system is necessary to determine any supplemental parts needed.
Installation Procedure
The installation process involves several key steps, as outlined in the provided documentation.
- Solenoid Mounting: The electrical solenoid valve, the core component of the line lock, must be securely mounted. The documentation recommends mounting it in an area such as the firewall, away from heat sources like headers and exhaust pipes, as well as steering and suspension components. This is to prevent flexing of the brake lines, which could lead to system failure.
- Brake System Identification: Before proceeding, it is essential to determine whether the vehicle is equipped with an SAE or metric brake system. The kits are specifically designed for SAE systems.
- Brake Line Connection: The solenoid body has two threaded ports. One port, marked “master,” must be connected to the brake master cylinder, and the other, marked “brake,” must be connected to the front wheel cylinders. The documentation from Malibu Racing specifies the use of DOT-grade or better brake lines for this connection.
- Bending Brake Lines: If bending brake lines is necessary, a tubing bender should be used to avoid kinking or crushing the lines. A line fitting wrench should be used when tightening fittings to ensure proper sealing and prevent damage.
- Air Bleeding: After installing the fittings and brake lines, the brake system must be bled to remove any trapped air. Vehicle manufacturers’ brake bleeding procedures should be followed.
- Leak Check: Following the bleeding process, all connections must be thoroughly checked for leakage under pressure. The documentation emphasizes that there must be no leakage.
- Operational Check: Before driving the vehicle, the entire brake system should be checked for proper operation, ensuring a firm and solid brake pedal. The line lock system should be tested several times to verify correct functionality.
Electrical Connections and System Activation
The line lock is activated electrically, requiring a connection to the vehicle’s electrical system. The documentation from Malibu Racing details the wiring of the solenoid. The system typically incorporates a micro-switch that, when pressed and held, activates the solenoid, applying the line lock. Releasing the switch releases the line lock. The documentation instructs to reconnect the battery, jack up the vehicle, secure it with jack stands, turn on the ignition, and then test the system by having someone activate the electrical system, press the brake pedal, hold the micro-switch, and then release the brake pedal.
Important System Considerations
Several critical considerations are highlighted in the documentation:
- Residual Valve Master Cylinder: If using an aftermarket brake system, a residual valve type master cylinder is required for proper line lock operation.
- Brake Fluid Compatibility: Only DOT-grade or better brake lines should be used.
- Post-Installation Testing: The documentation strongly advises against driving the vehicle until the brake system has been thoroughly tested and confirmed to be operating correctly.
- Metric vs. SAE Systems: The line lock kits are not compatible with metric brake lines or fittings. Using them with metric systems will result in improper sealing and potential system failure.
Conclusion
Installing a line lock requires careful attention to detail and a thorough understanding of brake system components. Proper mounting of the solenoid, correct brake line connections, and meticulous air bleeding are crucial for safe and reliable operation. The documentation emphasizes the importance of using compatible components (SAE thread systems only) and conducting comprehensive post-installation testing before operating the vehicle. Failure to adhere to these guidelines could result in brake system failure and potentially hazardous driving conditions.