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DESCRIPTION & OPERATION
E-TECH™ ENGINE DESIGN
FEATURES
The E-Tech™ engine evolved from the E7 PLN
(commonly referred to as the E7). The four
primary design features that differentiate the
E-Tech™ engine from the E7 engine are as
follows:
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Electronic Unit Pump (EUP) fuel injection
system
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V-MAC
®
III electronic control system
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Poly-v belt drive system
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J-Tech™ engine brake system from Jacobs
These major changes resulted in subsequent
improvements and redesign of related
components within the engine.
Electronic Unit Pumps
Electronic Unit Pump (EUP) technology, which
has been utilized in the heavy-duty industry for
many years, has been adapted for the E-Tech™
engine to achieve:
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Optimum performance
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Lower emissions
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Simplified service
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More effective pump/engine diagnostics
(individual cylinders can be isolated)
An EUP is a single-plunger fuel-injection pump,
one per cylinder, driven by a third lobe on the
engine camshaft. The pump roller follower
(tappet) is in contact with the engine cam lobe.
The EUP is very similar to a unit injector. The
primary difference is that the EUP delivers fuel
through a fuel injection line to a conventional-
style nozzle-holder assembly, whereas a unit
injector has a nozzle mounted directly on it.
The EUP is capable of providing very high fuel-
injection pressures. The pump is controlled by a
high-speed solenoid valve (see Figure 4)
responding to electronic signals from the
V-MAC III engine control module. This electronic
control provides a greater timing range. The
combination of higher pressures and greater
timing control improves the combustion process
and optimizes engine performance. This enables
the E-Tech™ engine to conform to more stringent
emissions regulations while providing
performance and fuel economy improvements.
4
Figure 4 — EUP Components
Electronic unit pumps for engines produced
through approximately late 3rd quarter 2000 were
fitted with three O-rings on the pump housings.
Pumps on engines produced later than 3rd
quarter 2000 are fitted with two O-rings in the top
and bottom grooves. The O-ring in the center
groove has been eliminated.
5_106_00.bk Page 14 Friday, August 4, 2000 11:17 AM
BDC for engine manuals and specs