How is the pressure controlled in the fuel injection system?
At engine start and for preheating the fuel when temperatures are low, the rail pressure is controlled by the PCV. To heat up the fuel quickly, the high-pressure pump delivers and compresses more fuel than is needed and the excess fuel is discharged by the PCV into the fuel return.
How does the heui system 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 do you need to know about the HEUI system?
3. Run a Quality Oil. The oil in a HEUI injection system works harder than any other engine oil in the world. Not only is it pressurized between 500 psi and 3,600 psi in the high-pressure circuit, but it is additionally responsible for lubricating and cooling the rest of the engine.
How is the oil pressurized in a HEUI system?
The oil in a HEUI injection system works harder than any other engine oil in the world. Not only is it pressurized between 500 psi and 3,600 psi in the high-pressure circuit, but it is additionally responsible for lubricating and cooling the rest of the engine.
How does the duty cycle work in a HEUI system?
Duty Cycle —The portion of time during which the IPR is active. In the HEUI system, it’s often given as a percentage (top number on the gauge) and is a vital aspect to monitor during diagnosis or performance applications to ensure the high-pressure oil pump is keeping up with oil demand.
Is the HEUI still used in Caterpillar engines?
Although HEUI would still technically be employed in later engines (the 6.0L Power Stroke, Navistar VT365 and MaxxForce DT), due to these engines using injection system components from Sturman Industries (and Caterpillar owning the term HEUI), you’ll find that the HEUI acronym doesn’t exist in any engine literature.