Fuel Injection Nozzle Check
Where ideal conditions of good combustion, specified engine temperature control and absolutely clean fuel prevail, nozzles require little attention. Nozzle trouble is usually indicated by one or more of the following symptoms: Smoky exhaust (black)
Loss of power
Increased fuel consumption
WARNING: Be extremely careful to prevent being struck by diesel fuel under pressure. Diesel fuel at injection pressure can easily pierce the skin, possibly causing severe injury from blood poisoning. If struck by pressurized diesel fuel, seek medical help immediately.
When faulty nozzle operation is suspected on an engine that is misfiring or puffing black smoke, a simple test can be made to determine which cylinder(s) is causing the problem. Run the engine at the RPM which makes the problem most pronounced. Momentarily loosen the high-pressure fuel inlet line connection on one nozzle assembly one-half to one turn. Then, tighten connection to specification. Check each cylinder in the same manner. If one nozzle is found where loosening makes no difference in the misfiring, or the puffing black smoke stops, that nozzle should be tested. Test only the suspect nozzle(s).