-·
-
CARBURETOR
Th
e pilot circuit.
The
pilot circuit
meters
the
air-fuel
m•xture
at idle and at
small
throttle
openings.
The
pilot
c
ir
cuit
consists
of
a
senes
of
passages
in
th
e carburetor body, o pilot
jet
to
mete
r
fuel.
and o pilot
sc
rew.
In
some
mod
els
, t
he
pdot
scre
w
meters
the air flow
through
th
e p
il
ot c
ir
cui
t. This
system
is
used
on
the
s
l•
de-typc co
rbu
•eto•s
In
othe1
models
the
p•lot setew controls
the
amount
of
awfuel mixture flowing
through
the
pilot circuit.
lhis
version
is
no•mally found on CV carburetors.
...
NOTE
:
On
some
carburetors
the
air
jets
are
l
oc
ated
in the top
part
of the
...
carburetor
b
ody,
underneath
the
diaphragm.
When
cleaning
or
replacing
them,
care
should be
tak
en
that
they
are
not interchanged.
Poor
performance
will
r
esu
lt
.
TIPS
:
l)A
p1
lo1
circu1
1t
hot 1S 1
00
leon
wd
1 cause lower
tha
n normal
CO
readi
ngs
and
low-lo-
no
rmo
l H
C.
If the leon condi
hon
1s
severe
eno
ugh
to
cause leon misf
ire,
th
e HC
readings
wi
ll
be very high. A machine w
it
h
thi
s condition wi
ll
us
ually experience o
hes
ll
ot
i
on
j
ust
o
ff
or
idle.
2)A
pdol circuit
that
IS
rich will cause higher
than
normal
CO
readings and
normal-to-
high
HC
, depend1ng on
how
severe
the
condi
tion
is.
A machine with
this
condition
w1ll
g•ve poor
fuel
economy and. usually. poor performance
os
well.
Fuel
fa•
th
e pilot cucu1t 1s drown t
hr
ough
the
pilot
jet.
which protrudes into
th
e float bowl.
Air for
th
e pilot c
ir
cuit
en
ters through o
small
pass
age in
the
inlet
si
de
of
th
e
ventu
ri
and,
in some model
s.
is
metered
by
the pilot
sc
rew.
Th
is
screw is tapered to p
rovi
de
a
g1adual
tncreose in air fl
ow
os
the
screw is backed
out.
MIKUNI
uses
two different types
of
pdot
jets
in
its
carburetors.
One
is
the
primary
type.
wh1ch
has only
the
metering hole drilled
through
its
entire length.
The
other
is
lhe air-bleed type. which
has
o
series
of
holes
drilled
thr
ough
its
sides
These
air bleed holes co
rr
espond wirh t
he
pdot
c
ir
cu
it
air passag
e.
As
air
fl
ows
through
th
ese
holes. the
fu
el b
ub
bl
es.
ond becomes pa
rt
ially ato
mi
zed before en
te
ring
the
ve
nt
u
ri
air
st
ream
c
TIPS:
NOTE
: Although
these
jets
are
the
sa
me physical siz
e,
th
ey
should not
be
interchanged.
lnterchang1
ng
the
pdot 1e1s
•es
ul
is
•n p
00
1
pc
do1
rnonce
.
If
t
he
prima
ry
ty
pe is 1eplaced
wi
th the air-bleed type a very rich cond
iti
on wi
ll
ex
ist
at
idl
e.
0
0
-
@
r
I)
Spurgo ouo I
1\or
oleeo
•2) Pn
mo
11n
l
~en70
spurgo
nr•o
t I Prrmory
(n
on-oir bleed}
0.33
To Next Page
Loading...
