With the Florida CDL Driver Handbook, you can examine up on the worries that especially relate to earning your CDL endorsement.

You are watching: How can you test that air flows to all trailers


Table of Contents

6. Combicountry Vehicles

Use the seven-step inspection procedure described in Section 2 to examine your combination automobile. Tbelow are more points to examine on a mix car than on a single vehicle. (For example, tires, wheels, lights, reflectors, etc.) However, there are also some brand-new things to examine. These are disputed listed below.

6.5.1 - Additional Things to Check During a Walkabout Inspection

Do these checks in addition to those already detailed in Section 2.

Coupling System Areas


*
Figure 6-8
Check fifth wheel (lower). Secudepend installed to framework. No missing or damaged components. Enough grease. No visible area between top and also lower fifth wheel. Locking jaws roughly the shank, not the head of kingpin. See Figure 6.8. Release arm properly seated and also security latch/lock engaged. Check fifth wheel (upper). Glide plate securely installed to trailer structure. Kingpin not damaged. Air and also electrical lines to trailer. Electrical cord firmly plugged in and also secured. Air lines correctly connected to glad hands, no air leaks, correctly secured through sufficient sabsence for transforms. All lines free from damages. Sliding fifth wheel. Slide not damaged or parts lacking. Properly greased. All locking pins current and also locked in area. If air powered--no air leaks. Check that fifth wheel is not so far forward that tractor framework will hit landing equipment, or the cab hit the trailer, in the time of turns.

Landing Gear

Fully increased, no absent components, not bent or otherwise damaged. Crank handle in area and secured. If power operated, no air or hydraulic leaks.

6.5.2 - Combination Vehicle Brake Check

Do these checks in enhancement to Section 5.3: Inspecting Air Brake Equipment.

The following area describes exactly how to examine air brakes on combicountry vehicles. Check the brakes on a twin or triple trailer as you would certainly any kind of combicountry vehicle.

Check That Air Flows to All Trailers. Use the tractor parking brake and/or chock the wheels to hold the car. Wait for air press to reach normal, then push in the red "trailer air supply" knob. This will supply air to the emergency (supply) lines. Use the trailer handbrake to administer air to the business line. Go to the rear of the rig. Open the emergency line shut-off valve at the rear of the last trailer. You need to hear air escaping, reflecting the entire mechanism is charged. Close the emergency line valve. Open the service line valve to examine that organization push goes via all the trailers (this test assumes that the trailer handbrake or the business brake pedal is on), and also then cshed the valve. If you carry out NOT hear air escaping from both lines, check that the shut-off valves on the trailer(s) and also dolly(ies) are in the OPEN position. You MUST have air all the method to the back for all the brakes to occupational.

Test Tractor Protection Valve. Charge the trailer air brake system. (That is, build up normal air push and press the "air supply" knob in.) Shut the engine off. Step on and also off the brake pedal numerous times to alleviate the air push in the tanks. The trailer air supply regulate (also called the tractor security valve control) have to pop out (or go from "normal" to "emergency" position) when the air push drops into the press selection mentioned by the manufacturer. (Generally within the selection of 20 to 45 psi.)

If the tractor defense valve doesn"t job-related appropriate, an air hose or trailer brake leak can drainpipe all the air from the tractor. This would certainly reason the emergency brakes to come on, with feasible loss of control.

Test Trailer Emergency Brakes. Charge the trailer air brake system and also examine that the trailer rolls easily. Then sheight and also pull out the trailer air supply control (likewise called tractor protection valve regulate or trailer emergency valve), or location it in the "emergency" place. Pull gently on the trailer with the tractor to check that the trailer emergency brakes are on.

Test Trailer Service Brakes.

See more: How Are The Equator And Prime Meridian Alike, What Are The Equator And The Prime Meridian

Check for normal air push, release the parking brakes, relocate the car forward progressively, and apply trailer brakes with the hand control (trolley valve), if so equipped. You must feel the brakes come on. This tells you the trailer brakes are associated and also working. (The trailer brakes need to be tested via the hand also valve however regulated in normal procedure with the foot pedal, which uses air to the business brakes at all wheels.)


Subarea 6.5Test Your Knowledge

Which shut-off valves should be open up and which closed? How can you test that air flows to all trailers? How have the right to you test the tractor protection valve? How can you test the trailer emergency brakes? How have the right to you test the trailer business brakes?

These questions might be on your test. If you can"t answer every one of them, re-review subsection 6.5.