PRODUCT INFORMATION
INDEX
DATE
Dep. 2
IO-G-T-00-001e B
February 2016
GAS ENGINES TROUBLESHOOTING
9/10
SYMPTOM
PROBABLE CAUSE
REMEDY
High exhaust gas emissions
Excessively advanced ignition
Check with a stroboscopic lamp and re-time
as necessary
Carburetion maladjustment
Readjust carburettor mixture valve.
(1)
Check MAP and MAT sensors signal
(2)
Check NOx sensor or lambda sensor signal
(3)
Ignition failures
Check spark plugs, high-voltage wires and
ignition coils
Change in gas quality
Readjust carburettor mixture valve.
(1)
Dirty air filters
Change air filters
Excessive vibrations
Incorrect alignment of engine
Re-align
Fasteners loose
Retighten fasteners
Defective damper
Change damper
Wrong crankshaft counterbalance
Re-balance
Loose flywheel
Retighten flywheel fasteners
Unusual noise
Knocking
Stop engine and check cylinders
Overload
Check power signal
Excessive valve clearance
Re-adjust valve clearance
Sticking valves
Repair valves
Piston hits jet
Change jet
Pin failure
Change pin
Excessive crankshaft end play
Replace main bearing thrust rings.
Gears in bad condition
Change defective gears
Leak in intake or exhaust
Locate and repair leaks
Excessive fuel consumption
Leak in gas system
Locate and repair leaks
Incorrect ignition advance
Adjust timing with a stroboscopic lamp
Combustion failure in a cylinder
Check coils, wires and ignition spark plugs
Incorrect air-fuel mixture
Readjust carburettor mixture valve
(1)
Check MAP and MAT sensors signal
(2)
Check NOx sensor or lambda sensor signal
(1)
Overload
Recalibrate power signal
(1)
Engines with mechanical carburetion
(2)
Engines with electronic carburetion
(3)
Engines with NOx sensor or lambda sensor carburetion
6.1.9
O&M_2.002211.810_A_10_2016