Page 466 - Foton Workshop Manual - Auman EST-M

DI - 412 Diagnosis - Mechanical fault diagnosis
Engine fault

Overview

Cummins ISF3.8 engine is a water-cooled, inline-four cylinder, four-stroke engine. The central fuel injector is
more favorable to full mixing of oil and gas and can, in combination with high-pressure common rail fuel
system and internationally leading Cummins combustion technology, effectively ensure the higher power and
torque of complete engine. Fukude Cummins ISF3.8 engine has the features of strong power, low oil
consumption, high reliability, low noise and vibration, good startability, low operating cost, etc. The vehicle
engine, as the power source of a vehicle, is very complicated structurally. Therefore, there are many and
diversified reasons to cause engine fault.
Failure phenomenon list
Failure phenomenon Possible reason Failure elimination

Check the battery and replace it if
Battery voltage too low
necessary
Clean the battery and tighten the
Battery cable loose and corroded
connection

Check the starter and replace it if
Starter failure
necessary
The engine fails to start
Measure the high pressure oil pump and
High pressure oil pump failed
replace it when necessary
Fuel filter blocked and fuel system too Clean the fuel system and replace the
much impurities fuel filter

Other relevant electric parts working Check relevant electric parts. Replace
abnormal them if necessary
Valve timing not correct Check the valve timing
Cylinder gasket leaking Replace the cylinder gasket

Measure the cylinder pressure. If
Cylinder pressure value too low
necessary, perform service
Check the valve and valve seat. Replace
Valve stem seal no good
them if necessary
Engine dynamic not sufficient Replace the fuel filter, clean the injector
Injector poor atomization
and if necessary, replace them
Exhaust system exhausting not smooth Check the exhaust system
Not adequate air for intake system Check if the intake system

Valve timing not correct Check the valve timing
Other relevant electric parts working Check relevant electric parts. Replace
abnormal them if necessary

DI-412