Page 312
SPECIFICATIONS
Pistons
Two-piece articulated, steel crown with three rings, aluminum
alloy skirt, pin bushings (early production), bushingless
(current production). The crown of bushingless pistons is
manganese-phosphate coated.
Piston rings — compression
Keystone, plasma-faced top ring. Rectangular, chrome,
tapered-face second ring
Piston ring — oil
Dual chrome-faced rails, conformable with coil spring
expander
Piston pin
Full-floating, 2.25-inch (57-mm) diameter, full-pressure
lubrication through rifle-drilled holes in connecting rod
Connecting rods
Forged steel, I-beam type with tapered pin end, 35-degree
cap angle, 10.4 inches (264 mm) center-to-center length
Crankshaft
Drop-forged, medium carbon steel, elotherm-hardened
journals and fillets, eight integral counterweights, 3.25-inch
(83-mm) pin journal diameter, 4.5-inch (114-mm) main journal
diameter
Bearings — main
Steel back, cast copper-lead intermediate layer, lead-tin
overlay
Bearings — connecting rod
Steel back, cast copper-lead intermediate layer, lead-tin
overlay, deltawall
Vibration damper
Constructed with internal metal inertia ring, viscous fluid filled
Camshaft
Carbon steel with induction-hardened journals and lobes,
gear driven
Valves — inlet
Poppet type with positive rotators, 20-degree seat, two per
cylinder
Valves — exhaust
Poppet type with positive rotators, 30-degree seat, two per
cylinder
Valve lifters
Roller follower type
Oil filters
Two spin-on disposable; one Centri-Max
®
Air compressor
Flange-mounted, gear driven, oil-lubricated and water-cooled
from engine; Bendix, Holset or Meritor WABCO
Turbocharger
Radial-flow type, exhaust gas driven, oil lubricated from
engine; Schwitzer
Lubrication system
Full pressure, wet sump, 28-quart (26.5 L) capacity,
25,000-mile (40 000-km) highway/300-hour stop-and-go
change interval; MACK-approved EO-M oil. If application
meets Line Haul 1 requirements, it qualifies for extended
service interval with MACK-approved EO-M Plus oil.
Valve seat inserts
Pressed-in head, replaceable
Manifold — air inlet
Two piece, six port
Manifold — exhaust
Three piece, six port
Manifold — water
Two piece, four port
Fuel injection pumps
Electronic unit pumps, Bosch
Fuel supply pump
Gear type, Bosch
Fuel injection nozzles
8-hole, 140-degree spray angle, Bosch
Fuel filters
Spin-on disposal type with metric mounting threads
Water pump
Centrifugal-rotor type, belt driven
Thermostat
180-degree opening with rubber-seated flange seal and
stainless steel caged check-ball vent
Coolant conditioner (optional)
Spin-on type, disposable
Item
Description
5_106_00.bk Page 312 Friday, August 4, 2000 11:17 AM
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