Resetting trailer surge brakes involves retracting the hydraulic actuator after it’s been compressed during braking. Typically, this is achieved by either manually pushing the actuator back into its housing and engaging a latch or locking mechanism, or by bleeding the brake lines to relieve pressure if the actuator is stuck. The specific method depends on your trailer brake system’s design and the reason for the reset.
Understanding Surge Brakes: The Foundation of Proper Resetting
Surge brakes, also known as inertia brakes, are a self-contained braking system that utilizes the momentum of the trailer to activate its brakes. Unlike electric brakes, which require electrical connections, surge brakes rely on a hydraulic actuator located at the trailer’s tongue. When the tow vehicle decelerates, the trailer’s momentum pushes against the actuator, compressing it and forcing brake fluid into the trailer’s brake cylinders, thereby applying the brakes.
The crucial aspect of surge brakes lies in their ability to automatically apply and release braking force. However, situations arise where resetting them becomes necessary. This could be after a hard braking event, after disconnecting the trailer from the tow vehicle (especially on a downward slope), or simply as part of routine maintenance. Incorrect resetting, or neglecting to reset at all, can lead to brake drag, reduced braking efficiency, and even damage to the braking system.
Step-by-Step Resetting Procedures
The exact procedure for resetting surge brakes varies depending on the type and manufacturer. However, the following are the most common methods:
Manual Retraction and Latch Engagement
This is the most common type.
- Identify the Latch Mechanism: Locate the latch or locking mechanism on the actuator housing. This is often a simple pin, lever, or spring-loaded catch designed to hold the actuator in the retracted position.
- Retract the Actuator: Manually push the actuator back into its housing. This may require some force, especially after heavy braking. Wearing gloves can help with grip.
- Engage the Latch: Once the actuator is fully retracted, engage the latch mechanism to secure it in place. Ensure the latch is securely engaged to prevent the brakes from accidentally applying during transport.
- Verify Proper Function: After latching, slightly tug on the actuator to ensure it is indeed locked in place and will not release prematurely.
Bleeding the Brake Lines (For Stuck Actuators)
If the actuator refuses to retract manually, trapped air or excessive fluid pressure may be the culprit. Bleeding the brakes may be required.
- Gather Necessary Tools: You will need a brake bleeder wrench, a clear hose, a container to collect the brake fluid, and fresh brake fluid that is compatible with your brake system (usually DOT 3 or DOT 4).
- Locate the Bleeder Screws: Find the bleeder screws on each of the trailer’s brake cylinders. These are usually located near the top of the cylinder.
- Attach the Hose: Attach one end of the clear hose to the bleeder screw and place the other end into the container of brake fluid. This prevents air from being drawn back into the system.
- Open the Bleeder Screw: Using the brake bleeder wrench, slightly loosen the bleeder screw (typically about a quarter turn).
- Retract the Actuator Manually: While the bleeder screw is open, attempt to manually retract the actuator. You should see brake fluid flowing through the hose and into the container.
- Close the Bleeder Screw: Once the actuator is fully retracted, tighten the bleeder screw.
- Repeat for All Brakes: Repeat this process for each brake cylinder, starting with the one furthest from the actuator.
- Top Off the Actuator Reservoir: After bleeding all the brakes, check the brake fluid level in the actuator reservoir and top it off as needed. Ensure you are using the correct DOT specification.
Safety Precautions
- Always wear safety glasses to protect your eyes from brake fluid.
- Avoid getting brake fluid on painted surfaces, as it can damage them.
- Dispose of used brake fluid properly according to local regulations.
- Consult your trailer’s owner’s manual for specific instructions and recommendations.
- If you are uncomfortable performing these procedures, seek assistance from a qualified trailer mechanic.
Regular Maintenance: Preventing Resetting Issues
Preventing frequent need for resetting involves regular maintenance.
- Inspect Brake Lines: Regularly check brake lines for leaks, cracks, or damage.
- Lubricate Actuator Components: Keep the actuator’s moving parts lubricated with a suitable grease or lubricant.
- Check Brake Fluid Level: Maintain the proper brake fluid level in the actuator reservoir.
- Inspect Brake Pads/Shoes: Regularly inspect brake pads or shoes for wear and replace them as needed.
- Service Actuator Regularly: Have the actuator professionally inspected and serviced periodically to ensure proper function.
Troubleshooting Common Problems
- Actuator Refuses to Retract: This is often caused by trapped air or excessive fluid pressure. Bleeding the brakes is usually the solution.
- Brakes Dragging: This can be caused by a malfunctioning actuator, worn brake components, or improper adjustment.
- Latch Mechanism Not Engaging: This may be due to rust, corrosion, or damage to the latch itself. Clean and lubricate the latch, or replace it if necessary.
FAQs: Your Questions Answered
1. What happens if I don’t reset my trailer surge brakes?
Failure to reset surge brakes can lead to brake drag, overheating, and accelerated wear of brake components. In severe cases, it can even damage the entire braking system and compromise safety.
2. How often should I check and reset my trailer surge brakes?
You should check your surge brakes before each trip and reset them as needed, particularly after disconnecting the trailer or experiencing hard braking. A more thorough inspection and possible reset should be conducted during routine maintenance checks.
3. Can I use WD-40 to lubricate the actuator components?
While WD-40 can provide temporary lubrication, it is not recommended for long-term use on actuator components. Use a lithium-based grease or a specialized brake lubricant for optimal performance and longevity.
4. What type of brake fluid should I use in my trailer’s surge brake system?
Refer to your trailer’s owner’s manual for the recommended brake fluid type. Most surge brake systems use DOT 3 or DOT 4 brake fluid. Using the wrong type can damage the seals and other components.
5. How can I tell if my surge brakes are working properly?
Properly functioning surge brakes should engage smoothly and progressively as the tow vehicle decelerates. There should be no excessive noise, jerking, or dragging. Also, ensure that the latch is correctly engaged when backing up.
6. My trailer surge brakes are locking up. What could be the cause?
Locking brakes can be caused by a malfunctioning actuator, seized brake cylinders, or contaminated brake fluid. Have the system professionally inspected to diagnose the problem.
7. Is it possible to convert my trailer surge brakes to electric brakes?
Yes, it is possible, but it requires significant modifications, including replacing the actuator, installing wiring, and adding an electric brake controller in the tow vehicle. This is generally not a DIY project and should be performed by a qualified professional.
8. What is the purpose of the breakaway cable on my trailer?
The breakaway cable is a crucial safety feature that automatically applies the trailer brakes if the trailer becomes detached from the tow vehicle. It should be connected to a separate point on the tow vehicle frame.
9. Where can I find replacement parts for my trailer surge brakes?
Replacement parts can be found at most trailer supply stores, auto parts stores, and online retailers. Be sure to order the correct parts for your specific brake system.
10. Can I adjust the sensitivity of my trailer surge brakes?
Some surge brake actuators have an adjustable dampening mechanism to control the sensitivity. Refer to your owner’s manual for instructions on how to adjust this setting.
11. What are the signs that my surge brake actuator needs to be replaced?
Signs of a failing actuator include difficulty retracting, leaking brake fluid, reduced braking performance, and excessive rust or corrosion.
12. How do I prevent rust and corrosion on my trailer surge brakes?
Regular cleaning with fresh water and a mild detergent, followed by application of a corrosion inhibitor, can help prevent rust and corrosion. Pay particular attention to the actuator and brake lines.