New Holland LS140 Workshop Manual page 39

Pistons and Connecting Rods
Pistons are cast from high silicon aluminum alloy and
are heat-treated for low weight with high strength and
good thermal conductivity. The piston is fitted with
three rings; two cast
compression rings and one steel, chrome-faced oil
control ring. The fully floating gudgeon pin (wrist pin)
is made of chrome molybdenum steel alloy hardened
by carburizing and retained by the conventional
retaining ring method. The connecting rods are
machined from high-strength forged steel. The big
end bearings are renewable
copper/lead alloy overlay with tin plating. The small
end bearings are a press fit plain bushing of
tin-backed lead/bronze.
Camshaft
The camshaft is made of forged steel and is induction
hardened. Three additional lobes at the front operate
the fuel injection pump. At the rear, a fuel lift pump
eccentric is machined. The camshaft is supported by
roller and needle bearings and lubricated by splash
feed. The nose of the camshaft supports the cam
gear, governor weight cage, and governor slider
assembly.
Cylinder Head
The cylinder head is made of high grade copper
chrome cast iron, and incorporates replaceable
heat-resistant alloy steel valve seats. Inlet and
exhaust valves are made
heat-resistant alloy steel with tuftrided stems and
induction hardened heads. Each stem is fitted with a
chrome molybdenum steel cap for long life.
The valves are operated by cold drawn seamless
tube push rods with hardened steel ball and forged
cup ends. Flat-based tappets are made from case
carburized chrome molybdenum steel operating in
machined bores in the cylinder block. The rocker
shaft is an induction hardened hollow steel tube.
Valve clearances are adjusted by hardened
ball-ended screws and locknuts.
SECTION 10 - ENGINE
iron, chrome-faced
steel-backed,
of high grade
10-4
Rocker Cover and Inlet Manifold
The cover is made of cast aluminum with an air
intake, oil filler, and crankcase breather. It is located
in position by rocker post studs and secured by cap
nuts.
Gear Train
The gear train consists of three helical gears - the
crankshaft gear located by a woodruff key, the idler
gear houses the lube oil pump, and the cam gear
incorporates the governor weight cage.
Fuel System
A flange-mounted, Bosch-type fuel injection pump is
mounted in the cylinder block and operated by lobes
machined on the engine cam.
Lubricating System
A trochoid lobe oil pump located in the center of the
idler gear sends lubricating oil to the main oil galley
via a relief valve through a spin-on bypass oil filter to
the main oil gallery. The rockers are pressure fed via
an externally mounted oil pipe from the main oil
gallery to the cylinder head.
Cooling System
A belt-driven centrifugal water pump circulates
coolant via the internal water passages. The coolant
is radiator cooled and temperature controlled by a
conventional thermostat.
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