Page 474 - Foton Workshop Manual - Auman EST-M

DI - 420 Diagnosis - Mechanical fault diagnosis

Failure phenomenon Possible reason Failure elimination

Check if the piston and piston ring is broken. If
Engine too noisy Piston or piston ring worn or broken
necessary, replace them

Fuel grade not meeting the application or
Use high quality fuel to run the engine
fuel quality too bad
Air in fuel system Check if there is air in the fuel system

Coolant temperature higher than Refer to coolant temperature higher than normal
specification value—graually too hot failure diagnosis

Engine too Ceiling mechanism adjustment not correct Measure and adjust the top mechanism
noisy---combustion knock
Perform diagnosis to find the broken injector and
Injector failed
replace it when necessary
Camshaft timing not correct (after the
Check the gear driving system timing
engine is reassembled or serviced)

Check the piston installation position and if there
Pinstall assembled incorrectly
are bits on the top of piston

Check the engine oil level Verify if the engine oil
Engine oil level lower than specification scale caliberation and oil sump capacity is correct
Filling engine oil to specified level

Check if the engine oil is contaminated. If the
Engine oil too thin or diluted engine oil is contaminated, refer to the engine oil
contamination failure diagnosis

Check the engine oil pressure. If the pressure is
Engine oil pressure lower than
low, refer to the engine oil pressure failure
specification
Engine too noisy---main diagnosis
bearing
Main bearing screw loose, worn or not Check the the torque of main bearing screw and
correctly tightened check if the screw is worn

Main bearing broken or excessively worn,
Check if the main bearing is broken, worn
not correctly assembled or wrong bearing
excessively and if the part number is correct.
installed
Crankshaft journal broken or out-of-round Check the crankshaft journal

Flywheel or flexible connecting disc screw Check the flywheel or flexible connecting disc
loose or broken and installing screw

DI-420