Datsun 1800 Fuel Pump Testing/Removing/Dismantling/Inspection/Assembly; Datsun 1800 Carburetor: Idling Adjustment; Datsun 1800 Fuel Level Adjustment; Datsun 1800 Starting Interlock Valve Opening - Datsun 510 series Workshop Manual

The
type
D3034C carburettor has certain additional features
These include
a
power
valve mechanism
to
improve the performance
at
high speed
a
fuel
cut
off valve which
cuts
the fuel
supply
when the ignition key is turned
to
the off
position
and
an
idling
limiter to
maintain the emissions below
a
certain level
Sectional views of
the two
types of pumps
are
shown in
Figs
8 1 and B 2 An EP 3 electrical fuel pump is located in the
centre
of the
spare
wheel
housing
in the boot Fig B 3 shows
a
sectional view of the
pump
with its contact the
pump
mechanisms
solenoid relay and built in filter
The air cleaner
uses a
viscous paper type element which
should be replaced
every
40 000 km 24 000 miles Cleaning
is
not required
and should not be
attempted
The cartridge type fuel strainer incorporates a
fibre clement
which should be renewed
at
inervals
not
exceeding
40 000 km
24 000 miles Fit B 4 shows
a
sectional view of the assembly
The fuel lines should
not
be disconnected from the strainer when
the fuel tank is full unless absolutely
necessary
as
the strainer
is below the fuel level
FUEL PUMP Testing
Disconnect the fuel hose from the pump outlet Connect
a
hose with
an
inner diameter of
approximately
6
mm
0 024
in to
the pump outlet and place
a
container under the end of
the
pipe
Note that the inner
diameter of the
pipe
must not
be
too small
or
the
pipe will be incapable of delivering
the correct
quantity
of fuel when
testing
Hold the end of the hose above the
level of the
pump
and
operate
the pump for
more
than IS
seconds
to
check the
delivery capacity
The
capacity
should be
I 400
cc
3 24 U S
pts
in
one
minute
or
less The pump
must
be removed from the vehicle if it does
not operate or
if
a
reduced
quantity
of fuel flows from the end of the hose Remove
the
pump
from the vehicle and
test
as
follows
Connect the
pump to
a
fully charged battery If the pump
now
operates
and
discharges
fuel correctly the fault does
not
lie
in
the pump but
may
be attributed
to any
of the
following
causes
Battery voltage drop
poor
battery
earth loose wiring
loose connections blocked hoses
or a
faulty carburettor
If the
pump
does
not
operate and discharge
fuel when
connected
to
the
battery
then the
pump
itself is
faulty
and
must
be checked
as
follows
First make
sure
that current is
flowing
This will be indica
ted by sparking
at
the tenninals If
current
flows the trouble is
caused
by
a
sticking
pump
plunger
or
piston
The pump must
be dismantled in this
case
and the
parts thoroughly cleaned in
petrol
If the
current
does
not
flow
a
coil
or
lead wire is broken
and the pump
must
be renewed
A
reduced fuel flow is caused
by
a
faulty
pump inlet
or
discharged
valve
or
blocked filter
mesh The pump
must
of
course
be dismantled and serviced
as
necessary
FUEL PUMP
Removing
and
Dismantling
Remove the bolts
attaching
the fuel pump
cover
to the
floor
panel
see
Fig
B S
Remove the bolts
attaching the
pump
to
the
cover
2
Disconnect the cable and fuel hoses Withdraw the pump
Dismantle
as
follows
Slacken the locking band
screws
and
remove
the strainer
strainer
spring
filter strainer seal and
locking
band
Remove the
snap
ring Withdraw the four
screws
from the
yoke
and
remove
the
electromagnetic
ulJ
it Press the
plunger down and withdraw the inlet
vaive
the packing
and the
cylinder
and
plunger assembly
A defective eledrical
unit cannot
be dismantled
as
it
is
sealed and must be renewed
as a
complete unit
FUEL PUMP
Inspection
and
Assembly
Wash the strainer filter and
gasket
in
petrol
and
dry using
compressed
air Renew the filter and gasket if
necessary
Note
that the filter should be cleaned
every
40 000 km 24 000
miles Wash the
plunger piston
and inlet valve in
petrol
and
make
sure
the
piston
moves
smoothly
in the cylinder Replace
the
parts
if found
to
be defective
Insert the plunger assembly into the cylinder of the electri
cal unit and move the assembly up and down
to
make
sure
that
the
contacts
are
operated
If the
contacts
do
not
operate
the
electrical
unit is
faulty
and must
be renewed
Assembly is
a
reversal of the dismantling procedures tak
ing
care
to
renew
the
gaskets
as necessary
CARBURETIOR
Idling Adjustment
The D3034C carburettor fitted
to engines equipped
with
an
emission control system
must
be adjusted
as
described under
the
heading
IGNITION TIMING AND IDLING SPEED in the
section EMISSION CONTROL SYSTEM
Reference should be
made
to
carburettor
idling adjustment
procedures for the L14
L16
and LI8
engines
when
adjusting
the type DAK 340 carburettor fitted
to
the G 18
engine
A smooth
engine speed of approximately
550
rpm
should be attained in
this
case
FUEL lEVEL
Adjustment
DAK 340earburettor
A
constant
fuellevcl
in
the float chamber is maintained
by
the float and needle valve See Fig 8 6
If the fuel level does
not
correspond with the level
gauge
line it will be necessary to
care
fully
bend the float seat
until the float
upper
position
is
correctly
set
The clearance H between valve
stem
and float
seat
should
be I 5
mm
0 0059 in
with
the float fully lifted Adjustment
can
be carried
out
by carefully bending the float stopper 3
FUEL lEVEL Adjustment
D3034Ccarburettnr
The fuel level should correspond
with the level
gauge
line
Adjustment can
be carried
out
if
necessary
by changing
the
gaskets between the float chamber body
and needle valve
seat
The
gaskets
are
shown
as
item 4 in
Fig
B 7 When
correctly
adjusted there should be
a
clearance of
approximately
7
mm
0 027 in between float and chamber
as
indicated
STARTING INTERLOCK VALVE OPENING
The choke valve
at its
fully cl o sed
position automatically
opens the throttle valve
to
an
optimum angle
of 14
degrees
on
the type DAK 340 carburettor and 13 5 degrees
on
the D3034C
carburettor With the choke valve
fully
closed the clearance
G I
in
Fig
8 should be 1 I
mm
0 0433 in This clearance
S19