AIR SYSTEM Twice a Year Air Dryer drain cocks, or valves and checking for presence of water. Maintain the air compressor to prevent excessive oil by-pass. See your maintenance manual for details. The function of the air dryer is to collect and remove air system contaminants in solid, liquid and vapor form before they enter the brake system. It provides clean, dry air to the components of the brake system, which increases the life of the system and reduces maintenance costs. NOTE A small amount of oil in the system may be normal and should not, in it- self, be considered a reason to re- place the desiccant cartridge. Oil stained desiccant can function ade- quately.
Replace worn seals in valves and air motors as they are needed. NOTE Because no two vehicles operate under identical conditions, mainte- nance and maintenance intervals will vary. Experience is a valuable guide in determining the best main- tenance interval for any one partic- ular operation. A tablespoon of water found in the air tank would point to the need for a desiccant cartridge change. However, the following conditions can also cause water accumulation and should be considered before replacing the desiccant cartridge. 5 Air usage is exceptionally high and not normal for a highway vehicle.
This may be due to accessory air demands or some unusual air requirement that does not allow the compressor to load and unload (compressing Every 900 operating hours or 25,000 miles (40,200 km) or every three (3) months check for moisture in the air brake system by opening air tanks, 5-60 Y53-6077-1B1 (03/17)