Idling Adjustment; External View Of Carburetor - Datsun 1200 1971 Workshop Repair Manual

Fuel
Sptem
The
power
valve mechanIsm
IS
of
a vacuum
actuated boost type
and
Improves
hIgh speed
drivIng
The throttle
opener
control
system Incor
porates
a servo
diaphragm
The
servo
dIaphragm helps
open
the throttle valve
at
a
decreasIng speed
so as
to
reduce the
emISSIOn
of
hydrocarbons to
a
minImum
An
antI dlesehng
olen01d
IS
used
as
a means
of
preventIng
dlesehng
When the
IgnItIOn
key
IS
turned ofT the fuel passage Involved
In
the slow system
IS
closed and the fuel
supply
IS
shut down
completely
In the chok mechanIsm
an
electric
automatIc
choke
IS
used
to
automatically
con
trol the choke valve
operatIOn
durIng
the
war
m up
of the engIne
The carburetor for automatic transmiSSIOn
IS
eqUIpped
WIth
so
called dash
pot
that
IS
It
makes smooth deceleratIng
WIthout
engIne
stall
at any
operatIng
conditIOn
These carburetors
are
qUIte
SImIlar
In
ap
pearance
as
explaIned
above
except
the dash
pot
for the
automatIc transmISSion
model
Adjustment
Idhng Adjustment
Idle
mixture adjustment requIres
the
use
of
a
CO meter
When prepatlng
to adjust
Idle
mIxture It
IS
essentIal
to
have the
meter
thoroughly
warmed and cahbrated
Warm
up
the engIne
suffiCiently
ContInue engme operatIOn
for
one
mmute
un
der
ldhng speed
Adjust
throttle adjustIng
screw so
that
engme
speed
IS
800
rpm
m
N pos1tIon
for
automatic transmiSSIOn
Check
IgmtlOn
tl
If
necessary
adjust
It to
the
speCificatIOns
IgnItIOn
tImlo 800
rpm
Adjust
Idle
adJustmg
screw so
that CO
percen
tage
IS
1
5
0 50
at
800
ns
a
On
automatIc
transmiSSIOn
eqUipped
model check
must
be
done
In
the D poSItIon
Be
sure
to apply
parkmg
brake and
to
lock both front and
rear
wheels With wheel chocks
b Hold brake pedal
while
steppIng
down
on
accelerator
pedal
OtherWise
car
Will rush
out
dangerously
On automatIc
transmiSSIOn
eqUIpped
model
make
sure
that the adjustment
has been made
With the selector lever
In
N
posItIon
And then check the
specificatIOns
With the
lever
In
D
pOSitIOn
Insure that CO
percent
and Idle
speed
are as
follows
Idle
rpm
650
for Manual transmISSion
for
Automatic transmISSion
Fig
91 External
view
of carburetor
3