What is Cummins PT fuel system?
The pressure-time (PT) fuel system (Figure 5-13) is exclusive to Cummins diesel. engines; it uses injectors that meter and inject the fuel with this metering based on a. pressure-time principle. A gear-driven positive displacement low-pressure fuel pump. supplies fuel pressure.
What is a PT fuel system?
The PT fuel system consists of the fuel pump, supply lines, drain lines, fuel passages and injectors. Fuel Pump. The fuel pump is coupled to the fuel pump drive which is driven from the engine gear train. Fuel pump main shaft in turn drives the gear pump, governor and tachometer shaft assemblies.
How does a 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.
How does a PT pump work?
The PT (type G) VS fuel pump, is made up of four main units; the gear pump, standard governor, throttle and a VS (Variable Speed) governor. It cuts off fuel to the injectors above maximum rated rpm. During operation between idle and maximum speeds, fuel flows through the governor to the injectors.
How do you turn up a PT pump?
The quick and dirty way for more fuel on a PT pump is drill out the plug in the throttle shaft and turn the slotted screw out 1/4 to 1/2 a turn. This will not increase rpm, only fuel rate. To increase rpm you must shim the gov.
What is a Cummins 855?
Cummins 855 Big Cam The Cummins 855 Big Cam was the last real mechanical variable timing engine mass produced by Cummins in the 1976. The Big Cam replaced the small cam 855 and was the first engine by Cummins to meet the Clean Air Act and noise regulations of that time.
What is fuel injection pump?
An Injection Pump is the device that pumps fuel into the cylinders of a diesel engine. Traditionally, the injection pump was driven indirectly from the crankshaft by gears, chains or a toothed belt (often the timing belt) that also drives the camshaft.
Is the 7.3 HEUI a powerstroke?
HEUI systems were the first modern injection system that could pressurize fuel independently from engine RPM. HEUI applications included the 7.3L and 6.0L Powerstroke used between 1993.5 and 2007 by Ford.