No air pressure in secondary tank - TruckersReport.com Labelling of air pressure gauges varies, and some vehicles have additional air pressure gauges for other systems. Spartan volt, air primary, air secondary gages: mtnpush: iRV2.com General Discussion: 3: 04-16-2022 12:24 PM: Where are primary and secondary fuel filters located: FLYING BUTCH: Entegra Owner's Forum: 7: 07-22-2021 05:19 AM: Primary and Secondary Air Tanks Empty in 24 hours: deandec: Country Coach Owners Forum: 38: 11-14-2019 08:18 PM Fortunately, alternatives are available. Thats why diesel-powered Type A motorhomes usually are equipped with air brakes. These valves allow you to drain moisture from the tanks or completely depressurize the system to perform maintenance work on the system. Most chassis manufacturers set the governor to cut out at 130 psi and cut in at 105 psi. A detailed total system review revealed that even though more air compressors had been added, the piping delivery system had never been upgraded. The typical life expectancy of motorhome service brakes is 350,000 miles, so dont worry about wearing them out. 1 Year So, 50 psi multiplied by 30 square inches equals 1,500 pounds of force. Normal air brake system pressure range is around 690 to 828 kPa (100 to 120 psi). As noted, spring brakes are found only on drive axles. It ensures that a motorhome wont roll away should the air pressure drop; it also stops a moving coach in the event of a total failure of the air system. the blow-off is in operation on all shifts, all year. Information on the demand load profile is very valuable for setting up the air compressor control system and determining the feasibility of using a VFD. Copyright American Institute of Chemical Engineers. An understanding of how the components on the supply and demand sides interact is essential to the design and operation of an efficient compressed air system. On the secondary system, quick-release valves discharge air pressure from the front axle brake chambers to disengage the brakes. The brake adjuster has another function. Computer hung up on my end across desktops so I patched it straight in. Except where noted, illustrations courtesy of ArvinMeritor, Bendix and Dana. As well, when building air pressure, one sub-system will fill to approximately 100psi and then the other sub-system will fill. Use to drop to 0 prior to repairs. All rights reserved. Pay attention to the low air-pressure warning light and buzzer. An air dryer (8) is a device that condenses and eliminates most of the water from an air system. Even tiny ice particles can cause problems. The other is called the secondary system. Maintenance is key to sustaining successful long-term operation and maximizing equipment life. 2016 Freightliner Cascadia- secondary tank won't air up passed 60psi. When the brake pedal is depressed, air flows from the primary reservoir and through the primary portion of the dual-control foot valve to actuate the rear axle brakes. They operate by expanding a pair of shoes inside a spinning brake drum. Keep your compressed air dry and filtered to help eliminate dust and sludge, which helps prevent the formation of new leaks (2). Drain valves are on each tank. Each company we work with has specific experience requirements for their drivers. Taking a systems approach can help you devise solutions to these challenges. Air compressors are powered directly by the engine or by using belts and pulleys. The primary tank operates the rear brakes; the secondary tank operates the front brakes. Air compressors are generally most efficient when they are running fully loaded. Hydraulic brakes perform well on relatively lightweight motorhomes, but heavy vehicles need more braking capacity. When there is no pressure in the line(s) due to trailer breakaway or a gross air leak in the trailer circuit the valve closes to maintain air pressure in the tractor circuit. Reservoirs, three per tractor and, usually, two per trailer, store the compressed air until it is needed to actuate the brakes. Taking a systems approach can help eliminate ongoing system problems. Establishing a formal air leak search, tag, and repair program can help document and remedy FRL leaks. Only about 510% of the energy input to a compressor goes toward productive use of compressed air. Compounding can lead to premature cracking or breaking of brake drums, bent chamber push rods, mounting studs torn out of the spring brakes, broken slack adjusters, or torn spring brake mounting brackets on the axle.