Hartridge is pleased to announce the release of its latest tooling for Delphi authorised testing and repair of Delphi E3.3, E3.4, E3.5, E3.6 electronic unit injectors (EUI) and US 2010 Smart injector which are fitted with Zero Back Leak Nozzle (ZBLN). 

With injection pressures continuing to climb in the never-ending quest towards achieving near-perfect combustion, Delphi's latest generation electronic unit generators for medium and heavy duty applications are no exception. 

By eliminating back leak flow fuel consumption is improved by removing the energy wastage inherent in recycling the otherwise unspent fuel. 

Delphi E3.4 - E3.6 series injectors all share this design of nozzle. The main defining feature for the diesel workshop needing to replace ZBLN is that locating dowels are no longer used to position them in place.

Instead they have to be oriented according to a given datum point that aligns the nozzle holes in the correct way inside the main injector housing. 

The new Hartridge ZBLN tooling comprises of an alignment rig to firstly enable the replacement nozzles to be correctly located and then secondly a pre-load tool to ensure there is no unitentional movement when re-tightening the assembly. 

View of nozzle alignment through the microscope 

ZBLN Nozzle Alignment

Nozzle alignment is achieved using the position of the nozzle holes relative to a given datum point. Accuracy is an important factor for this design of injector and so the new tooling consists of two major elements: the first one being a method of nozzle alignment and the second being a means to apply the correct required compression to maintain the nozzle's position prior to tightening the cap nut. 

Do you want to find out what tools are required to test ZBLN injectors?