Page 62 - Draft 2023 2024 CDL Manual w Modernization Info

- SECTION 7-' DOUBLES AND TRIPI.ES

Connect Converter Dolly to Front Trailer • Apply converter gear spring brakes or chock » Locking jaws around the shank, not the
head of kingpin.
• Back first semitrailer into position in front wheels. » Release arm properly seated and safety
of dolly tongue. • Release pintle hook on first semi-trailer. latch/lock engaged.
• Hook dolly to front trailer. • Slowly pull clear of dolly. • Check fifth wheel (upper).
• Lock pintle hook. Never unlock the pintle hook with the dolly » Glide plate securely mounted to trailer
frame.
• Secure converter gear support in raised po­ still under the rear trailer. The dolly tow bar may » Kingpin not damaged.
fly up, possibly causing injury, and making it
sition. very difficult to re-couple.
Connect Converter Dolly to Rear Trailer • Air and electric lines to trailer.
» Electrical cord firmly plugged in and se­
• Make sure trailer brakes are locked and/or 7.2.3 - Coupling and Uncoupling cured.
wheels chocked. Triple Trailers » Air lines properly connected to glad
• Make sure trailer height is correct. (It must Couple Tractor/First Semitrailer to Second/ hands, no air leaks, properly secured with
Third Trailers
enough slack for turns.
be slightly lower than the center of the fifth
wheel, so trailer is raised slightly when dolly • Couple tractor to first trailer. Use the method » All lines free from damage.
is pushed under.) already described for coupling tractor-semi­ • Sliding fifth wheel.
• Back converter dolly under rear trailer. trailers. » Slide not damaged or parts missing.
» Properly greased.
• Raise landing gear slightly off ground to • Move converter dolly into position and cou­ » All locking pins present and locked in
ple first trailer to second trailer using the
prevent damage if trailer moves. method for coupling doubles. Triples rig is place.
• Test coupling by pulling against pin of the now complete. » If air powered, no air leaks.
» Check that fifth wheel is not so far forward
second semitrailer. Uncouple Triple-trailer Rig that the tractor frame will hit landing gear,
• Make visual check of coupling. (No space • Uncouple third trailer by pulling the dolly or cab will hit the trailer, during turns.
between upper and lower fifth wheel. Lock­ out, then unhitching the dolly using the Landing Gear
ing jaws closed on kingpin.) method for uncoupling doubles.
• Connect safety chains, air hoses, and light • Uncouple remainder of rig as you would any • Fully raised, no missing parts, not bent or
otherwise damaged.
cords. double-bottom rig using the method already
• Close converter dolly air tank petcock and described. • Crank handle in place and secured.
shut-off valves at rear of second trailer (ser­ • If power operated, no air or hydraulic leaks.
vice and emergency shut-offs). 7.2.4 - Coupling and Uncoupling Double and Triple Trailers
• Open shut-off valves at rear of first trailer Other Combinations
(and on dolly if so equipped). The methods described so far apply to the • Shut-off valves (at rear of trailers, in service
and emergency lines).
• Raise landing gear completely. more common tractor-trailer combinations. » Rear of front trailers: OPEN.
However, there are other ways of coupling
• Charge trailer brakes (push "air supply" knob and uncoupling the many types of truck-trailer » Rear of last trailer: CLOSED.
» Converter dolly air tank drain valve:
in), and check for air at rear of second trailer and tractor-trailer combinations that are in use.
by opening the emergency line shut-off. If air There are too many to cover in this manual. CLOSED.
pressure isn't there, something is wrong and You will need to learn the correct way to couple • Be sure air lines are supported and glad
the brakes won't work. and uncouple the vehicle(s) you will drive ac­ hands are properly connected.
cording to the manufacturer and/or owner • If spare tire is carried on converter gear
7.2.2 - Uncoupling Twin Trailers specifications. (dolly), make sure it's secured.
Uncouple Rear Trailer • Be sure pintle-eye of dolly is in place in pintle
• Park rig in a straight line on firm level 7.3 - Inspecting Doubles hook of trailer(s).
and Triples
ground. • Make sure pintle hook is latched.
• Apply parking brakes so rig won't move. Use the seven-step inspection procedure de­ • Safety chains should be secured to trailer(s).
• Chock wheels of second trailer if it doesn't scribed in Section 2 to inspect your combina­
tion vehicle. There are more things to inspect • Be sure light cords are firmly in sockets on
have spring brakes. on a combination vehicle than on a single ve­ trailers.
• Lower landing gear of second semitrailer hicle. Many of these items are simply more of
enough to remove some weight from dolly. what you would find on a single vehicle. (For 7.3.2 -Additional Things to Check
• Close air shut-offs at rear of first semitrailer example, tires, wheels, lights, reflectors, etc.) During a Walk-around Inspection
However, there are also some new things to
(and on dolly if so equipped). check. These are discussed below. Do these checks in addition to subsection 5.3,
• Disconnect all dolly air and electric lines and Inspecting Air Brake Systems.
secure them. 7.3.1 -Additional Checks
• Release dolly brakes. Do these checks in addition to those already 7.4 - Doubles/Triples
Air Brake Check
• Release converter dolly fifth wheel latch. listed in Section 2, Step 5: Do Walk-around In­
spection.
Check the brakes on a double or triple trailer
• Slowly pull tractor, first semitrailer, and dolly Coupling System Areas as you would any combination vehicle. Sub­
forward to pull dolly out from under rear section 6.5.2 explains how to check air brakes
semitrailer. • Check fifth wheel (lower). on combination vehicles. You must also make
Uncouple Converter Dolly » Securely mounted to frame. the following checks on your double or triple
» No missing or damaged parts.
• Lower dolly landing gear. » Enough grease. trailers
• Disconnect safety chains. » No visible space between upper and lower
fifth wheel.

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