Service manual
SERVICE
MANUAL·
1975
SCORPION
BRUT
ENGINE
SYSTEM
General
Description:
The
Scorpion
Brut
en
gine
is
especially
designed
and
built
for
today's
high
performance
snowmobile.
Any
internal
combusion
engine
performs
best
and
is
most
reliable
at
a
constant
operating
tem-
perature.
The
Scorpion
Brut
engine
is
ther
-
mostatically
controlled
to
run
at
a
180
degree+4
degree
F
cylinder
head
temperature
whether
the
outside
temperature
is
-30
degree
F
or
+50
degree
F.
This
close
temperature
control
reduces
to
a
minimal,
the
necessity
of
changing
spark
plugs
and
the
worry
of
piston
seizing.
However,
in
order
to
get
the
best
possible
use
and
ensure
that
it
retains
its
high
degree
of
dependability,
performance
and
endurance,
it
must
receive
proper
care
and
maintenance.
Therefore,
it
is
necessary
to
know
something
about
the
basic
fundamentals
of
this
engine
and
how
it
functions
.
OPERATION
The
Scorpion
Brut
engine
uses
a
mixture
of
gasoline,
oil
and
air
for
combustion,
lubrication
and
cooling
.
It
fires
on
every
strok
e
of
each
piston.
There
are
two
or
three
power
strokes
(depending
on
the
model),
for
every
revolution
of
the
crankshaft.
As
the
piston
moves
upward
in
the
cylinder,
it
draws
the
fuel/air
mixture
into
the
crankcase
through
the
intake
manifold
while
at
the
same
time
compressing
fuel
that
has
been
forced
into
the
combustion
chamber
(Fig.
1-1
A).
As
the
piston
nears
top
dead
center,
the
spark
plug
is
fired
and
the
compressed
fuel/air
mixture
burns
and
expands,
thereby
forcing
the
piston
downward
on
a
power
stroke.
As
the
downward
stroke
of
the
piston
turns
the
crankshaft,
it
a l
so
starts
to
compress
the
fuel/air
mixture
in
the
crankcase
and,
simultaneously,
opens
the
exhaust
po
rt
and
closes
the
intake
por
t
(Fig.
1-1
B & C).
1-2
)