Operation and Maintenance Manual for PowerKit 6M16 Series
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1. O-ring; 2. Gasket; 3. Fuel return hole of injector
Figure 2-4 Fuel return method
Internal fuel return through the cylinder head is adopted for6M16 four-valve diesel engine for
power generation (figure 2-4). In this manner, the injector mounting hole is located in the cylinder
head, so it should be ensured that fuel return is completely free of leakage.
2.3.2 Internal high-pressure connection
The high-pressure fuel comes to the injector via the fuel inlet joint inside the cylinder head. For the
high-pressure sealing of standard fuel inlet joint, the pre-tightening force should be at least 12kN,
and it should not exceed 22kN. Excessive pressure will result in leakage due to overload of the fuel
inlet joint.
When installing the fuel inlet joint, apply some oil to the O-ring and thread pairs. The screw threads
and shaft shoulder must also be oiled. The mineral oil is recommended. The oil to be used must be
suitable tothe materials of O-ring. For the O-ring and threads with the surfaces being lubricated
already, no oil is needed to apply.
Due to the lateral sealing force of fuel inlet joint, improper mounting of the joint will cause
inappropriate stress on the injector (the lateral force resulting from fuel inlet joint may cause bend
of the injector). The 5-step tightening method from previous practices is most suitable to minimize
the force deformation of injector.
