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38
Exhaust with abnormal smoke color
Possible causes and condition
Remedies
Exhaust with black smoke
deal with by the conditions of Insufficient
power
Exhaust with white smoke
①
Bad atomization of injector
②
Water in cylinder or diesel
③
Some cylinder doesn’t work when
operating at low speed on cold day
④
Incorrect fuel injection advance
angle
Check the working conditions; replace the
excessive blow-by if necessary.
Check diesel, if there is water in it, replace it,
Otherwise, check for damage of the cylinder
head parts which may cause water leak,
replace the damaged ones.
Close the shutter door when the ambient
temperature is low, and make the operating
temperature rise quickly to avoid running long
time at low temperature.
Check and adjust fuel injection advance angle
Exhaust with blue smoke
①
Too much oil in sump
②
Operation at zero load and low
speed for too long time
③
Sticking, much wear or inverse
installing orientation of piston
rings, oil blow-by and burn in
cylinder
④
Oil seeps through the gap
between valve guide and stem
due to valve guide is much worn.
Check the level of oil, drain it if necessary.
Decrease time of the operation at zero load
and low speed to avoid oil blow-by and burn in
cylinder
Replace the piston ring if necessary.
Check the clearance between the valve and
guide,
Replace it if necessary.