Datsun 1000 - Page 46

13 Fuel
System
3
Flat
spot
on acceleration
Possible cause
a Blocked
accelerator
pump
discharge
jet
or
sticking
check valve
b
Faulty accelerator
pump plunger
c
Faulty accelerator
pump
linkage
4
Engine
misfires or
cuts out at
high speed
Possible cause
a Obstruction
in main or
power jets
b
Low fuel
level in float
chamber or
float
chamber
starving
for fuel
c
Failure
of
fuel
pump
to
deliver
sufficien
t fuel
d
Blockage
in
fuel
tank
pipe
e Restriction
in
fuel
filter
f
Air leak
between
fuel
pump
and filter
or
between filter and tank
g
Air leak
between carburettor air
horn
and main
body
assemblies
or
main
body flange
h
Water
in
carburettor
5 Excessive
fuel
consumption
Possible cause
a Float level
too
high
b Choke
butterfly partially
closed
c Air
cleaner element
dirty
or
requires
renewal
d
Accelerator
pump requires
an
adjustment
or in
wrong
hole
in
pump connecting
link
e
Fuel
pump
delivery pressure
too
high
f Faulty
fuel
pump
diaphragm
g
Leaks
between fuel
pump
and
fuel
tank
or fuel
pump
and
carburettor
h
Power
jet
vacuum
plunger
stuck
in
release lower
position
i
Faulty
power jet
j
Worn or
damaged
main or
power
jets
k
Excessive use of choke or
accelerator
pump
Remedr
Clean and
blowout carburettor
Renew
pump
plunger
assembly
Check and rectify
pump
linkage
Check
that
pump connecting
link
is in
correct
position
in the
pump
lever
Remedv
Dismantle and blowout
jets
Check float level
setting
check
fuel
pump
filter and
supply
lines
Overhaul fuel
pump
Remove
blockage
and
clean
pipe
Clean
or
renew filter
Rectify
air
leak
Check
and renew
gasket
and
tighten
securing
screws
Drain and clean fuel
system
Remedy
Check
and
re
adjust
float level
Check
and
rectify
Clean
element or renew
Re
adjust
accelerator
pump
stroke
with
link
in
other hole oflever
Check
and
fit
correct
diaphragm
spring adjust
fuel
pressure
with
pump
base
gasket
Overhaul fuel
pump
and
renew as
necessary
Gleck
and
rectify
leaks
Free
plunger
or renew
Check
and renew
faulty
jet
Check and renew
faulty
components
Revise
driving
habits
46
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