SELVA MARINE Blue Whale 250 EFI, Service Manual

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GEN
INFO
General information
1-35
6P23H11
Engine speed control system
In the Blue Wlale 250 engine, the engine speed control system decreases the engine speed to protect
the engine from damage when the engine overheats or when the engine oil pressure is low.
Engine speed control
Description Control Engine condition
Overheat Detects when the engine overheats and
controls the engine speed. • Detects that the engine
is overheating when the
thermoswitch is turned
on or the engine temper-
ature exceeds 120
° C
(248 ° F).
• The ECM causes the
cylinders to misfire, cuts
off injection, decreases
the engine speed to less
than 2,000 r/min, acti-
vates the warning buzz-
er, and turns the over-
heat warning indicator
on.
Low oil pressure Detects when the engine oil pressure is low
and controls the engine speed. • Detects that the engine
oil pressure is low when
the oil pressure is less
than 250 kPa (2.5
kg/cm
2
, 36.3 psi) when
operating at engine idle
speed, and when all en-
gine speeds, except the
engine idle speed, are
below the standard val-
ue.
• The ECM causes the
cylinders to misfire, cuts
off injection, decreases
the engine speed to less
than 2,000 r/min, acti-
vates the warning buzz-
er, and turns the low oil
pressure warning indica-
tor on.