Function

The Diesel engine injection pump distributes an exactly defined amount of fuel at an exactly defined moment in time with very high pressure, according to the injection order, to the cylinders.

How it works

First of all, it is important that the fuel is well-filtered, containing no air or water. In order to inject into the compression stroke, the pressure in the compression space must be significantly higher than in the cylinder. To ensure a good atomizing withside combustion chamber systems and throttle pintle nozzles, 400 - 500 bar are necessary in the high pressure chamber of the injection pump. The nozzle opening pressure is at least 130 bar.For direct injections with sharply injecting hole type nozzles, the pressures are substantially higher. Distributor type injection pumps are equipped with one piston to provide the high pressure for all engine cylinders, in-line injection pumps have one piston per engine cylinder.
Mechanical injection pumps regulate the injection amounts through the centrifugal governor and the beginning of delivery by the injection control device.
The distributor type injection pump is quite characteristic when the Dieselengine is charged. The full load stop must be variabel to ensure more fuel. The pump is larger due to the diaphragm unit.

This is a scheme of a test bench for adjustment of the in-line injection pump. The distributor type injection pump does not have adjustment possibilities, but might be tested, too.

Important

The injection pump is driven by the crankshaft with half its speed.

Imprint