Water and contaminants should be drained from the primary air brake supply reservoir daily unless a reservoir drain valve (automatic type) is installed. Daily draining is not needed on reservoirs with the optional reservoir drain valve (automatic type). The reservoir drain valve (automatic type) automatically drains water and contaminants.

1. Start the engine and charge the system with air.



2. Pull the cable attached to the reservoir drain valve (manual type) on the bottom of the supply reservoir.
3. After the water and contaminants stop draining, release the cable. The reservoir drain valve (manual type) will close.

1. Block the wheels.
2. Apply the parking brake.



3. Drain the supply reservoir.

On reservoirs with a reservoir drain valve (manual type), pull the reservoir drain valve cable until the reservoir drain valve opens. Hold the cable until all the air is drained.




4. On reservoirs with a reservoir drain valve (automatic type), push upward on the wire in the exhaust port of the reservoir drain valve (automatic type) and hold until all the air is drained.
5. Open the reservoir drain valve (manual type) and drain the front service reservoir.
6. Open the reservoir drain valve (manual type) and drain the rear service reservoirs. Drain all of the rear service reservoirs.