Advantages of installing a booster pump on a diesel
If we return to the main topic, the booster pump for diesel is in many cases electric. Such a pump becomes an important element in the power system, as it allows not only to quickly and efficiently supply diesel fuel to the high-pressure fuel pump, but also to pass diesel fuel through filters.
Also, the presence of a booster pump allows you to achieve stable operation of the diesel engine in all modes and at any speed, that is, there is no shortage of fuel under load. We also note that many owners of diesel cars, who do not normally have an additional pump, decide to install it themselves.
This need can be dictated by various reasons, starting with a slight airing of the power system after parking and ending with the desire to facilitate the start of a diesel engine. The pump can be placed both in the fuel tank and integrated in certain sections of the fuel lines for diesel fuel supply after the tank.
As a rule, after installation, the owners note that the diesel engine is easier to start (you need to make fewer revolutions with the starter). There is also a more stable operation of the internal combustion engine in different modes (transient modes, XX, work under load). In some cases, an increase in power is also possible, since fuel is stably supplied to the high-pressure fuel pump even at high speeds.
Booster pump device and various types of low pressure fuel pumps
If we talk about the design, the low pressure fuel pump has the following components:
- Drive shaft
- Rotor with blades
- stator
- Distribution disk
- drive gear-regulator
- Couplings
The principle of operation is that the rotor begins to move first, as a result of which its blades approach the stator. As a result, under the influence of centrifugal force, “chambers” and a certain tension are created. Then, from the chambers, fuel enters the high-pressure fuel pump. Channels are made in the distribution disk for fuel supply. If the pressure exceeds the norm, part of the fuel is redirected to the pressure reducing valve.
Given that the booster pump and the high pressure pump are connected, in order to maintain the necessary conditions, there is a fuel drain throttle. The specified throttle is a jet that is screwed into the injection pump.
This solution allows you to maintain the desired conditions in the chambers, while taking into account the dependence on the speed at which the drive shaft moves. A similar scheme is well suited for diesel engines, while there are other types of booster pumps.
Varieties of low pressure fuel pumps
Let's start with the fact that a low pressure fuel pump is installed on any car, gasoline (carburetor, injector), and many diesel ones, but not all. This device "draws" the fuel from the fuel tank, after which the fuel passes through the filters, enters the dosing systems and is fed into the engine.
In this case, booster pumps are mechanical and electric. Gasoline carburetor ICEs have a mechanical pump, and injection engines have an electric fuel pump. However, if in gasoline counterparts, regardless of the type of engine, such a pump is the main one, in diesel engines, the booster pump supplies fuel to the high-pressure fuel pump.
A mechanical booster pump is usually placed on the cylinder block. Such a device is driven by the engine itself. Simply put, during the rotation of the motor, a special cam of the pump is pressed, as a result, the device begins to pump fuel into the carburetor. Also, the mechanical pump has a special lever, which allows you to manually pump gasoline before starting the engine.
An electric booster pump became a necessity after injection engines appeared. The fact is that for normal operation of the injector, fuel must be supplied to the nozzles at a higher pressure compared to carburetor internal combustion engines.
Naturally, a mechanical pump that is weak in performance is not able to cope with such a task. He was replaced by an electric fuel pump. Such a pump is actually an electric motor and a pumping chamber, which are generally combined in a housing. The supercharger is located directly in the gas tank and is immersed in fuel. Also, a fuel level sensor and a special filter mesh for fuel cleaning are integrated into the pump housing.
This solution has a number of advantages, since the device is more productive, and also does not overheat from excess heat in the engine compartment. Also, before starting the engine, there is no need to pump fuel manually, since after turning the ignition key, the booster pump starts immediately, raising the pressure in the power system.
It should also be noted that in the circuit with an electric pump, the fuel is constantly moving along the lines, which allows you to maintain a normal fuel temperature and avoid overheating.
Single acting fuel priming pump
The single-acting fuel priming pump consists of a housing in which a rod, a piston and valves are located.
Inlet 5 and outlet 1 valves with springs are installed at the fuel inlet and outlet in the housing in the pump housing. The pump drive is carried out from the eccentric 3 of the injection pump camshaft. The force is transmitted through the pusher to the piston drive of the fuel priming pump. The reverse stroke of the piston is carried out under the action of spring 6. The principle of operation of such a pump is as follows. When the eccentric 3 runs off the pusher 2, the pressure on the piston 4 from the side of the pusher disappears and under the action of the spring 6 the piston moves up. At the same time, inlet valve 5 closes, and outlet 1 opens and fuel enters the high-pressure fuel pump. When the eccentric 3 of the cam shaft runs on the rod 2, the piston 4 moves down. Pressurized fuel opens the inlet valve 5 and enters through the slots in the piston into the cavity above the piston.
