FACT FILE: DIGIPLEX DISTRIBUTOR
REMOVAL
25E. If the distributor has to be removed
for any reason, it is ESSENTIAL that the
PRECISE position of the rotor arm in
relation to the distributor body and the
position of the distributor body (2) in relation to the
cylinder head
-
via the spacer (1)
-
are clearly marked so
that they can be
replaced in
EXACTLY the
same position.
Note that the
locator
(arrowed) only
gives an approx-
imate, not a
precisely correct
location of the
spacer.
25F. D INSIDE
INFORMATION:
Use
touch-up
paint
and
let it
dry before
removing the
unit. D
SETTING THE RPM AND TDC SENSOR POSITION
25G. This job can not
be carried out without
the FIAT special tool
illustrated. The sensor
is correctly positioned
when the engine is
produced and to
prevent accidental
tampering, one of the
two bolts holding the
sensor in place is a
shear bolt and will have to be renewed if removed.
IMPORTANT NOTE: The slots in the distributor body are
NOT used to alter the advance setting, as on a conven-
tional distributor. This operation is carried out by the
position of the TDC sensor
-
see later.
CHECKING THE IGNITION ADVANCE can be carried out in an
approximate manner using the same method as described in
25C.
However, you must make sure that the following steps
are
taken:
•
the
vacuum pipe between the electronic control unit and
the
inlet manifold must remain connected and be in good
condition
-
neither blocked nor split.
•
the
engine must be at its normal operating temperature.
•
the
idle speed/mixture/CO adjustments must be correct
-
see Job 35.
•
with
the engine idling at between 800 and 900 rpm, the
mark on
the crankshaft pulley should be at approximately 12
degrees BTDC.
IMPORTANT NOTE: The only marks are for 0, 4 and 10
degrees BTDC, so you will have to make a guess at the
correct position for 12 degrees.
FACT FILE: TIMING MARKS
y-; • It appears that some earlier engines
H. j may be fitted with different types of
J timing marks. There might be a metal
pointer fitted to the timing belt cover.
Other engines may have their timing marks in the
flywheel housing, so that you need to take out a rectan-
gular rubber bung and look out for the fixed timing
mark on the flywheel housing and the timing settings
on
the flywheel itself.
• It always helps to paint all of the timing marks with
white paint or typists' correction fluid so that they are
easier to see when the timing light is operating.
1. Line up the mark on the crankshaft pulley with the 0
degrees (TDC) mark on the timing belt cover. See 25C.
2. Without moving the crankshaft from this position, undo the
screws holding the rpm and TDC sensor to the sensor carrier
plate. Fit the tool no. 1895898000 in place of the sensor.
Check that the flywheel pin or lug (3) must fit in the groove of
the tool and the bolts must tighten easily. If not, carry out the
following procedure:
3. Slacken the bolts securing the carrier plate behind the
sensor.
4. Move the plate so that the tool slips freely into the sensor's
hole and the bolts tighten easily.
5. Tighten the bolts holding the sensor carrier plate in place.
6. Remove the tool and refit the sensor.
ON BOTH TYPES: As the distributor is turned (clockwise to
advance, anti-clockwise to retard), the timing mark on the
flywheel will be seen to move relative to the pointers. Move
the distributor so the timing marks are aligned correctly, and
retighten the clamp nut or bolts.
• Job 26. Check/adjust drive belt/s.
26A. Depending on
your Tipo or Tempra
model, access to the
alternator belt and
adjustment fixings will
probably be possible
from the engine bay.
V-BELTS ONLY
Check the belt, and if there is any sign of cracking, 'polishing',
fraying or severe wear on the inner face, replace it. The belt
should deflect by about 10 mm when firm thumb pressure is
applied to the belt between the pulleys in the direction of the
arrow. Too little tension and the belt might slip; too much,
and belt and bearing wear will increase.
IMPORTANT NOTE: • All Tipo/Tempra diesel engines are
self-bleeding and there should be no need to bleed air
out of the system manually.
• If the engine does not eventually re-start, check all the
unions for the fuel inlet pipe and the other unions,
replacing the sealing washers if necessary, to eliminate
any air leaks.
Q Job 35. Check/adjust petrol engine idle and
emissions.
Setting the idle speed and mixture is not just a matter of
making
the car run smoothly and economically; it's also a
question of allowing it to run within the legal hydrocarbon
(HC), Nitrous Oxide (NO) and carbon monoxide (CO) emission
limits. If it
is
outside limits, the car will fail the annual test.
(However, a worn engine will fail even if the carburettor or
injection system is correctly set up.)
FACT FILE: ESSENTIAL
PREPARATIONS
• When tuning the engine you should
adjust the carburettor (when fitted) last
of all, as its settings will be affected by
the state of tune of the rest of the engine.
• Ignition dwell angle and timing must be correct, the
air
filter
should be clean, there should be no air leaks
on
the induction system, and all electrical components
and
the air conditioning (if fitted) should be switched
off.
• Get the engine to full operating temperature before
checking and adjusting.
• If
you
warm the engine on tick-over (instead of on a
journey), it won't be hot enough until you have heard
the electric cooling fan cut in twice.
Q INSIDE INFORMATION: These jobs require the use of a
tachometer (rev-counter) and an exhaust gas analyser to
achieve any degree of accuracy. If you don't own them -
and relatively inexpensive tools are now available
-
you
may
wish
to have the work carried out by your local FIAT
dealer. D
ROUGH
GUIDE: Within each section is a description of how
you
can
get the car running tolerably well without any
specialist
equipment, so that you can take it to your FIAT
dealership
for accurate (and MoT-able!) tuning.
35A. Check the float
level with the carburettor
in the position shown.
Distance (c) should be
30mm with gasket fitted.
Bend tab (2) to adjust
-
but the tab should
remain virtually perpen-
dicular. Do NOT adjust
items (1)or (3)1
35B. IDLE SPEED
ADJUSTMENT: Connect a
rev-counter according to
the maker's instructions,
and check the idle speed.
clockwise increases the
idle speed, anti-clockwise
reduces it. Set the idle
speed in accordance with
Chapter
3,
Facts and
Figures.
ROUGH GUIDE: Turn the screw until the engine is running at
the slowest speed at which it runs smoothly and evenly.
MIXTURE ADJUSTMENT: Check that the idle speed is correct
and make sure that the engine is at full operating temper-
ature. Connect an exhaust gas analyser as instructed by the
maker. If the CO reading is outside the range shown in
Chapter
3,
Facts and Figures, adjustment as follows:
Use a narrow-blade screwdriver and turn the screw (2)
clockwise to weaken (reduce) or anti-clockwise to richen
(increase) the reading.
ROUGH GUIDE: Turn the mixture screw inwards (clockwise).
As you do so, the tick-over speed will increase, until the point
comes where the engine starts to run 'lumpily'. Back off the
screw until the engine runs smoothly again, and then some
more until the speed just starts to drop. At this point, screw
the adjuster back in by a quarter-turn and you'll be
somewhere near the optimum setting for smooth running.
IMPORTANT NOTE: After setting the mixture adjustment,
re-check and, if necessary, re-adjust the idle speed.
CARBURETTOR MODELS ONLY
TAMPER PROOFING: All Tipo carburettors originally had a
tamper-proof seal placed over the mixture adjustment screw.
These
seals are to prevent anyone unauthorised from altering
the
mixture and exhaust emissions. In certain countries these
seals
must be retained by law.
If the
seal
is
a plastic cap placed over the adjuster screw, it can
be
broken
off with pliers. If it is a plug within the screw recess,
force
it out with a sharp object.
35C. This illustration
shows the correct
settings for the
choke fast idle
adjustment (manual
choke only) and the
automatic anti-
flooding device
adjustment. See
following page.
Q Step B11: Undo the belt tensioner nut (see illustration
Job 13-B10, part d), then remove the timing belt.
Q Step B12: Undo the nuts securing the brake vacuum
pump to the cylinder head (see illustration Job
16-1),
and
remove it.
• Step B13: Fit FIAT tool no. 1860932000 (for setting
camshaft timing) to the vacuum pump end of the camshaft,
matching the camshaft groove (1) with the lug (2) on the tool
Secure
the tool to the cylinder head, positioning the centring
dowel
(3) as shown. The dowel must be perfectly centred on
the tool,
and if it isn't, you should adjust the hexagonal bolt
(4) with
a spanner, and centre it with tiny movements.
• Step B14:
Remove
the bolt
(arrowed) which
secures
the front
cover
to the engine
block,
then fit the
timing belt on the
crankshaft sprocket.
• Step B16:
Lock the injection
pump sprocket (see
StepA13). Now,
using FIAT tool no.
1860831000,
slacken the bolt
securing the
camshaft sprocket.
• Step B17: Continue fitting the timing belt in the
following sequence: crankshaft sprocket, fixed tensioner,
injection pump sprocket, timing sprocket, belt tensioner... and
check that the mark on the injection pump lines up with the
fixed mark on the rear cover.
• Step B18: Use the timing belt tensioner to correctly
tension the belt.
B INSIDE INFORMATION: If you do not have the correct
tensioning tool, follow Steps A16 and A17. B
• Step B19: Tighten the camshaft sprocket bolt to the 1
specified torque (see Chapter
3,
Facts and Figures).
Q Step B20: Turn the crankshaft by two revolutions
(clockwise), tighten the belt tensioner to the specified torque
(see Chapter
3,
Facts and Figures) and remove the
tensioning tools. If the belt is correctly tensioned you should
just be able to twist it through a quarter-turn when gripping it
between thumb and finger in the centre of its longest run
between sprockets. Adjust as necessary.
O Step B21: Refit the remaining components in the reverse
order of removal, then check the injection timing. See
Chapter
5,
Servicing Your Car, Job 25.
Job 14. Diesel engine.
Cylinder head - removal.
• Disconnecting the high pressure pipes on a diesel
injection system can be dangerous!
• Read the Safety First! information at the start of
PART F: FUEL AND EXHAUST SYSTEMS before
starting work.
Q Step 1: Refer to Job
13
and remove the timing belt.
• Step 2: Drain the cooling system and disconnect the air
pipes from the inlet manifold.
Q Step 3: Disconnect
and remove the oil vapour
pipes from the cylinder
block device.
Job 13-B13
• Step B15: Fit
FIAT tool
No.
1860933000 for
precise
determination
of TDC
on cylinder
No. 1. The
tool must
be secured
firmly by
two bolts
to the
crankshaft sprocket,
and by
another bolt
to the
crankshaft front cover (where the bolt was previously
removed in Step B14).