Mack ASET AC, Service Manual

Page: 87 / 536

Page 74
DESCRIPTION AND OPERATION
86
Figure 86 — Sectioned View, Front of ASET™ Engine Block
OIL PUMP
Due to the addition of an idler gear, the auxiliary
shaft on the ASET™ and E-Tech™ engines
rotates in the opposite direction of the E7
auxiliary shaft. However, in order to maintain the
same pumping direction and lubrication oil flow
for both ASET™/E-Tech™ and E7 engines, the
oil pump drive gear helix is reversed on the
ASET™ engines (Figure 87). With the reversed
drive gear helix, the driving thrust load of the
shaft pumping gears is toward the pump housing
and not toward the pump cover, as with the E7
engine.
앫
An improper drive gear on the oil pump will
prevent oil pump installation, assuming a
correct gear is on the auxiliary shaft.
앫
If an oil pump and an auxiliary shaft
assembly were replaced, two improper
gears could be installed, and engine failure
would result.
앫
In replacing any of these critical parts,
always refer to part number information in
the MACK Parts System to ensure the
correct component is being used.
5-111.bk Page 74 Monday, July 10, 2006 2:26 PM