Are heui injectors adjustable?
Although injection pumps are often adjustable to some extent, the characteristics of injection events are relatively fixed. HEUI systems, however, are electronically controlled and injection events and characteristics can be commanded dynamically based on various parameters.
How many wires does a HEUI injector have?
Both the HEUI-A and HEUI-B systems use a single solenoid with two wires, but the HEUI-B injector has a unique valve concept where a single solenoid controls both the oil pressure to the intensifier, as in the original system, and also the oil pressure to control the nozzle check.
How do heui injectors work?
Opposed to the prior single-shot fuel injection design, HEUI systems use an electronically controlled hydraulic activation with a high-pressure oil pump forcing a plunger within the injector to open the needle to fuel spray into the combustion chamber.
What is a unit injector used for?
The unit injector system allows accurate injection timing, and amount control as in the common rail system . The unit injector is fitted into the engine cylinder head, where the fuel is supplied via integral ducts machined directly into the cylinder head.
What does cat do on a C7 HEUI?
CAT (Electronic Technician) software is used to calibrate injector trim codes preceding dyno testing. CDs are included with C7 HEUI Running Complete format engines for injector/ECM recalibration during engine installation.
Why was the cat HEUI injector system introduced?
The limitations of mechanically governed fuel systems that were first introduced in the 1950’s and 60’s were quickly becoming an issue. The primary disadvantage is that mechanical systems pressurized fuel by either an injection pump driven by the camshaft or a gear driven low pressure fuel pump (used by Cummins).
What kind of fuel does a cat C7 ACERT use?
In 2007 diesel fuel itself changed to Ultra Low Sulfur Diesel or ULSD. The fuel change dictated that the fuel system of the CAT C7 ACERT needed to change to a common-rail injection system. The new common-rail injectors took injection pressures to 25,000-27,500 psi. The fuel transfer pump supplies the fuel to the fuel rail at 280 psi.
What is the fuel delivery system on a cat C7?
The fuel delivery system on the CAT C7 is hydraulic electronically controlled unit injectors for the mid horsepower models and mechanically actuated and electronically controlled on the higher horsepower models. Both systems are metered and timed to inject multiple bursts of fuel to create a more efficient combustion cycle.