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(III) Unstable Speed of Diesel Dngine
Fault Characteristics & Causes
Elimination Approaches
1. Fuel pipe
a) Air exists in supply system.
b) Excessive water content is included in fuel.
c) Fuel pipe leaks.
a) Exhaust the air in the fuel system and tighten
the connections of the fuel pipe
；
b) Replace the fuel
；
c) Tighten the connections of the fuel pipe or
replace the pipe.
2. Speed governor works improperly.
Adjust and calibrate the speed governor.
3. Cylinder head gasket performs bad sealing.
Check the bolts and the gasket of the cylinder
head. Tighten the bolts or replace the gasket.
4. Cylinders supply oil differently.
a) Injection pump has different oil supplies from the
cylinders;
b) Injector performs badly or the matching parts
are seized.
c) Piston spring for injection pump is broken.
a) Adjust the oil supply from the cylinders to
injection pump;
b) Check the situation of injection, clean or
replace the matching parts;
c) Replace the spring.
