NMC-WOLLARD 140 - Cooling Sytem; Description of the Tractor; Engine; Equipment Description

NMC-WOLLARD 2021Truax Blvd., Eau Claire, WI 54703, Phone (715) 835-3151, Fax (715) 835-6625
M140 Tow Tractor Manual No. 46054
PAGE 1-5
CHAPTER 1 GENERAL INFORMATION AND OPERATING INSTRUCTIONS
1 DESCRIPTION
1.4 EQUIPMENT DESCRIPTION
1.4.1 Intended Use
It is not to be used on public roads. Do not perform high speed maneuvers.
The tractor is designed for towing aircraft but may also be used for towing
other loads. Towing couplers may be attached to the front and/or rear of the
tractor. Its drawbar pull capacity is 8,000 to 14,000 lbs.
1.4.2 Description Of The Tractor
The tractor operates like most any automotive vehicle powered by an internal
combustion engine. The major difference between this tractor and an
automobile having a similar size engine is the higher gear ratio in the rear
axle. The higher gear ratio allows great pulling (towing) ability. Maximum
forward speed is between 12 and 23 MPH, depending on axle gear ratio.
1.4.3 Frame
The frame is a welded-steel one-piece unit, cross-braced to prevent
misalignment. Ballast weight is on the frame over the rear axle. An adjustable
driver’s seat is on the left side of the tractor. A seat may also be provided on
the passenger side.
1.4.4 Engine
A diesel or gas engine powers the rear wheels through a transmission, drive
shaft, and rear axle assembly. The engine is a valve-in-head, four-cycle,
liquid-cooled, pressure-lubricated, with crankcase ventilation.
1.4.5 Cooling Sytem
The water pump on the front of the engine circulates coolant through the
cylinder block, head, radiator, and oil cooler. A belt-driven cooling fan creates
air ow through the radiator to lower the temperature of the coolant as it
passes through the radiator. To allow higher water temperatures without
boil-over, the system is pressurized. If system pressure exceeds 14 PSI (due
to excessive heat), a valve in the radiator ll cap will open to release the
pressure.
To maintain proper engine operating temperature, a thermostat regulates
water ow from the engine to the radiator. When coolant reaches 182ºF, the
thermostat begins to open, and is fully open at 192ºF.
1.4.6 Transmission
The automatic transmission and torque converter housing are together in an
aluminum casting. Gear selection is done by using a conveniently located
manual shift lever. On most tractors, the lever has ve detent positions; R
(reverse), N (neutral), D (drive), 2 (second), and 1 (low).
AUGUST 31, 2008