With a hydraulic unit injector, the build-up of fuel pressure is provided by hydraulic pressure and not with a camshaft as with the mechanical unit injector. This allows for more installation freedom. In fact, there is no need to have a camshaft nearby. These units are also called HEUI. Hydraulic Electronic Unit Injector and are mainly used in the industrial and truck sector. There is quite a range of HEUI types, with Diesel Büchli having access to the stock of good suppliers in addition to its own stock.
To ensure proper operation, it is very important to carefully follow the manufacturer’s installation instructions. Clean work is an absolute necessity in this respect. Naturally, any cause of injector failure must be eliminated prior to installation.