Mitsubishi S6S-Y3T61HF Service Manual page 12

INTRODUCTION
Other cautions
Modification of engine prohibited
Unauthorized modification of the engine will void the
manufacturer's warranty.
Modification of the engine may not only cause engine
damage but also produce personal injuries.
Never break the seals
To ensure proper engine operation, the fuel control link
is provided with seals that protect the fuel injection vol-
ume and rotation speed settings against tampering. If
these seals are broken and the settings are changed,
proper operation of the engine will no longer be guar-
anteed, and the following problems will be expected to
occur.
• Rapid wear of moving and rotating parts
• Engine troubles such as damage and seizure of
engine parts
• Increased consumption of fuel and lubricating oil
• Deterioration of engine performance due to poorly
balanced fuel injection volume and governor opera-
tion
Pre-operational check and periodic inspec-
tion/maintenance
Be sure to perform the pre-operational checks and pe-
riodic inspection/maintenance as described in this
manual.
Neglecting the pre-operational check or periodic in-
spection/maintenance can arouse various engine trou-
bles such as damage to parts, eventually leading to
serious accidents.
Break-in operation
A new engine needs to be broken in for the first 50
hours of operation. During this period, do not subject
the engine to heavy loads.
Operating a new engine under high loads or severe
conditions during the break-in period can shorten the
service life of the engine.
VIII
CAUTION
Warming-up operation
After starting the engine, run the engine at low idling
speeds for 5 to 10 minutes for warming-up. Start the
work after this operation is completed.
Warm-up operation circulates the lubricant through the
engine. Therefore, individual engine parts are well lu-
bricated before they are subjected to heavy loads. This
is very important for longer service life, high-perfor-
mance and economical operation.
Do not conduct warm-up operation for a longer time
than necessary. Prolonged warm-up operation causes
carbon build-up in the cylinders that leads to incom-
plete combustion.
Avoid engine operations in a overload con-
dition
If the engine is considered to be in an overloaded con-
dition which is identified by too much black smoke, etc.,
immediately reduce the load on the engine such that
the correct output and load conditions may be
achieved.
Overloading the engine causes not only high fuel con-
sumption but also excessive carbon deposits inside the
engine. Excessive carbon deposits can cause various
engine problems and shorten the service life of the en-
gine remarkably.
Cooling operation before stopping engine
Always conduct the cooling operation (low speed
idling) for 5 to 6 minutes before stopping the engine.
Abruptly stopping the engine immediately after high-
load operation can cause partial overheating and short-
en the service life of the engine.
During cooling operation, check the engine for abnor-
malities.
Protection of engine against water entry
Do not allow rainwater, etc. to enter the engine through
the air inlet or exhaust openings.
Do not wash the engine while it is operating. Cleaning
fluid (water) can be sucked into the engine.
Starting the engine with water inside the combustion
chambers can cause the water hammer action which
may result in internal engine damage and serious acci-
dents.