The Specifications for a Champion 720A Motor Graderby Tim McQuade
The 720A motor grader is a maintenance or construction machine manufactured by Champion. The "A" in the 720A refers to the articulated chassis design of this grader. Grader chassis are either articulated or rigid, with articulated chassis providing more flexibility. Champion is now owned by Volvo.
The Champion 720A motor grader uses a Cummins C8.3 engine that has a rated power output of 160 horsepower at 2,200 rpm, and peak torque of 560 foot-pounds at 1,500 rpm. The C8.3 meets EPA and CARB emission requirements without being equipped with after-treatment or catalysts. For fuel economy, the C8.3 burns 0.397 pounds per horsepower-hour at 2,200 rpm.
The Cummins C8.3 used a four-cycle, inline six-cylinder design. The engine featured a turbocharged system. The C8.3 Tier 1 featured a Jacket Water After-cooled system; however, Cummins redesigned the C8.3 and produced the C8.3 Tier 2, which utilized a charge air-cooled (air to air) cooling system. Total engine displacement measures 506 cubic inches, or 8.3 liters. The bore by stroke measures 4.49 by 5.31 inches. The engine features two valves per cylinder, totaling 12 valves. The Tier 2 version also sports pre-painted, powder coated, cylinder head castings, which reduces engine corrosion. An efficient Bosch P3000, in-line fuel pump with RSV governor, makes up the fuel system on the C8.3. The C8.3 engine measures 44.4 inches long, 29.5 inches wide and 43.2 inches tall. The oil system holds 37-19 quarts of oil, and the cooling system holds 12 quarts of coolant. The wet weight of the engine is 1,360 pounds.
The Champion 720A uses a Champion model No. 8400 transmission. This transmission uses a fully sequential, direct drive, power-shift design that sports a single-lever transmission. The clutch uses a multi-disc, flywheel mounted and oil-cooled design. At 2,200 rpm, the transmission motivates the 720A to 2.7 mph in first gear, 3.8 in second, 5.3 in third: 7.4 in fourth, 10.4 in fifth, 14.4 in sixth, 20.2 in seventh and 27.9 in eighth. In reverse, the 720, at 2,200 rpm, could travel up to 2.7 mph in first, 5.3 in second, 10.4 in third and 20.2 in fourth.
The 720 used a Champion model No. SR30 differential and final drive. This unit featured a single reduction final drive that utilized an operator controlled lockable differential. The rear axle also used a case hardened, full floating design that was supported on double row, spherical roller bearings.
The 720 used fade resistant, hydraullically actuated, oil disc service brakes that were located at the four tandem wheels. The brakes are also self-adjsuting, fully sealed and this reduced brake maintenance needs.
The 720A grader weighs 32,570 pounds. Blade-down pressure -- which is the max downward force applied at the cutting edge -- measures 16,717 pounds. Max blade pull weight measures 20,657 pounds. Total weight on the front wheels measures 9,615 pounds; on the rear wheels, it measures 22,955 pounds. The 720's typically equipped moldboard and sacrificer measures 14 feet by 25 inches by 7/8 inch, and is made of S.A.E. high carbon steel. The moldboard's edge is 6 by 5/8 inch, and is made of boron steel.
The tire size measured 14 by 24 inches, No. G-2. The ply rating was 12 pr. and the rim size measured 10 inches. Total ground clearance on the front axle measured 24 inches. The minimum turning radius measured 25 feet 6 inches while the steering arc measured 72 degrees.
The fuel tank held a 100 gallon limit. The transmission had a maximum capacity of 10.2 gallons and the final drive could hold 6 gallons. Each Tandem held 26.4 gallons and the hydraulic oil tank held 23.8 gallons. The engine oil tank held a max of 5.9 gallons.
The front axle uses a fully welded steel struss, which oscillates on a single 3.5-inch diameter center pivot pin. The wheel lean measures 18 degrees to the right and left. The oscillation measures 16 degrees up and down. This also features a four-inch diameter wheel lean cylinder with a standard lock valve. The steering system utilizes two steering cylinders and has power front-wheel steering. The frame design features twin, 4.5-inch hydraulic cylinders with a 22-degree right and left frame articulation. The 720's circle is 66.25 inches in diameter, 1.25 inches thick, and has three adjustable guide shoes and clamp plates. The circle drive has a 360-degree rotation.
- grader road construction image by Francois du Plessis from Fotolia.com