Do you know how to inspect the air brake system on your Stoughton trailer? Before driving a vehicle with an air brake system, it is essential to ensure the system is functioning properly before setting off. The pros at Ainsworth Trailer Repair in Denver offer these tips for checking your vehicle’s air brake system. Checking these components should be part of your regular fleet trailer maintenance routine.
Important Safety Procedures for Checking Air Brake Systems
Before checking your air system, make sure your Stoughton trailer is parked on a level surface, with spring brakes applied and wheel chocks/blocks in place before beginning your inspection. It is imperative you never leave the cab or get under a vehicle before performing this procedure.
Essential Air System Components to Check Before Each Trip
- Spring brakes
Check the effectiveness of spring brakes by gently applying engine power with the brakes engaged. If the vehicle moves, spring brakes are defective. Next, verify the automatic application of trailer spring brakes. Open the trailer supply valve (push in). Make sure the system is fully charged. Pull out the trailer supply valve to close it and listen for the spring brakes to apply. If they do not automatically apply, they are defective. - Low air pressure warning devices
Begin with the system at pressure (90psi). Turn the ignition on, noting primary/secondary air tank pressure readings. Press and release the brake repeatedly, listening for the low pressure warning. If the device activates at or above 55psi, it passes. If the device does not activate or activates below 55psi, it is defective. - Compressor
Your compressor must be able to restore pressure to normal range rapidly. When pressure is reduced to 80psi, and the trailer supply valve closed (pulled out), the system should be able to return to proper pressure (100psi) during vehicle idle within 2 minutes, otherwise, it is faulty. - Compressor governor settings
Determine the normal operating pressure range for your vehicle (based on make/model year). Run the vehicle until maximum pressure is reached, noting cut-out setting. Then, press and release the brake repeatedly to lower pressure, noting cut-in setting. A cut-out above 145psi or cut-in below 80psi indicates a faulty governor. - Tractor protection valve
Disconnect the trailer service line and apply the service brakes. With the trailer supply valve closed, listen for air escaping from the trailer service line. Any exhaust indicates a defective valve. - Drain valves
Drain each air tank, observing discharge. If valves don’t function properly or motor or oil is emitted, the system is defective. - Checking for system leaks
When the system is under full pressure, with engine off, spring brakes released, and service brakes applied, check air loss by monitoring pressure gauges and listening for audible leaks. If the pressure drop within one minute exceeds manufacturer specs, the system is defective.
Is your air brake system blown? Get your rig back to roadworthy with the help of Ainsworth Trailer Repair shop. We know your livelihood depends on your Stoughton trailer. We pride ourselves on addressing repair issues in hours, not days. Contact us for a competitive repair quote or to schedule air brake system maintenance today.
