Page 816 of 873

86ELECTRICAL
2
FAULT DIAGNOSIS LUCAS CONSTANT ENERGY IGNITION SYSTEM -
V8i
Preliminary checks
Inspect battery cables and connections to ensure they
are clean and tight. Check electrical condition of
battery.
Inspect all L.T. connections, ensure they are clean
and tight. Check H.T. leads are correctly positioned
and not shorting to ground against any engine
components. Wiring harness and individual cables
should be firmly fastened to prevent chaffing.
Pick-up air gap
Check air gap between pick-up limb and reluctor teeth
is 0.20 - 0.35 mm, using a non-ferrous gauge.
NOTE: Air gap is set initially at factory and
will only require adjusting if tampered with
or when pick-up module is replaced.
TEST 1:
H.T. Sparking
Remove coil/distributor H.T. lead from distributor
cover and hold approximately 6mm from engine block,
using suitable insulated pliers. Switch ignition 'On' and
operate starter.
Regular sparking indicates fault in H.T. distribution,
plugs, timing or fuelling, proceed to Test 6. If no spark
or weak spark occurs proceed to Test 2.TEST 2:
L.T. Voltage
Switch ignition 'On' - engine stationary.
(a) Connect voltmeter to points in circuit indicated
by V1 to V4 and make a note of voltage
readings.
(b) Compare voltages obtained with specified
values listed below:
Expected readings
V1 More than 12 volts.
V2 1 volt maximum below volts at V1.
V3 1 volt maximum below volts at V1.
V4 0 volt - 0.1 volt.
(c) If all readings are correct proceed to Test 3.
(d) Check incorrect reading(s) with chart to identify
area of possible faults, i.e. faults listed under
heading SUSPECT and rectify.
(e) If coil and amplifier is suspected, disconnect L.T.
lead at coil, repeat V3. If voltage is still incorrect,
fit new coil. If voltage is now correct, check L.T.
lead, if satisfactory fit new amplifier.
(f) If engine will not start proceed to Test 3.
Page 820 of 873

ELECTRICAL
1
ADJUSTMENT IGNITION TIMING
Service repair no - 86.35.15
Adjust
1.It is essential that following procedures are
adhered to. Inaccurate timing can lead to serious
engine damage and additionally create failure to
comply with emission regulations. If timing is
being checked in vehicle, air conditioning
compressor must be disengaged.
2.On initial engine build, or if distributor has been
disturbed for any reason, ignition timing must be
set statically to 6°B.T.D.C.
NOTE: This approximate setting is made
only to ensure that engine may be started.
CAUTION: On no account must engine be
started before this operation is carried out.Equipment required :-
Calibrated Tachometer
Stroboscopic lamp
3.Couple stroboscopic timing lamp and tachometer
to engine following manufacturer's instructions.
4.Disconnect vacuum hose from distributor.
5.Start engine. With no load, and without
exceeding 3,000 rev/min run engine until normal
operating temperature is reached. (Thermostat
open). Check that engine idles within tolerance
specified in data section.
6.Idle speed for timing purposes must not exceed
800 rev/min.
7.Run engine at idle speed and check timing using
stroboscope light on timing marker and pointer.
WARNING: Keep hands and equipment
away from belt.
8.If timing is not as specified, switch off engine.
Loosen distributor clamp bolt and turn distributor
to advance or retard ignition as necessary.
Tighten clamp bolt, start engine and recheck
timing.
WARNING: Personal injury may result if an
attempt is made to adjust distributor whilst
engine is running.
9.Upon completion, switch off engine and retighten
distributor clamping bolt securely. Recheck
timing, to ensure retightening has not disturbed
distributor position.
10.Refit vacuum hose.
11.Disconnect stroboscopic timing lamp and
tachometer from engine.
Page 825 of 873

ELECTRICAL
5
REPAIR ELECTRONIC IGNITION - V8i
A Lucas 35DLM8 distributor is employed. This has a
conventional vacuum advance unit and centrifugal
automatic advance mechanism.
A pick-up module, in conjunction with a rotating timing
reluctor inside distributor body, generates timing
signals. These are applied to an electronic ignition
amplifier module mounted on side of distributor body.
NOTE: Pick-up air gap is factory set. Do
not adjust gap unless pick-up is being
changed or base plate has been moved.
Use a non-ferrous feeler gauge to set air gap.
IGNITION COIL
Service repair no - 86.35.32
Remove
1.Disconnect battery negative lead.
2.Noting their fitted positions, disconnect electrical
leads from ignition coil.
3.Remove two bolts securing ignition coil clamp,
recover suppressor.
4.Remove coil.
Refit
5.Reverse removal procedure.DISTRIBUTOR - V8i
Service repair no - 86.35.20
Remove
1.Disconnect battery negative lead.
2.Disconnect vacuum hose.
3.Remove distributor cap.
4.Disconnect low tension lead from coil.
5.Mark distributor body and centre line of rotor
arm.
6.Add alignment marks to distributor and front
cover.
NOTE: Marking distributor enables
refitting in exact original position, but if
engine is turned while distributor is
removed, complete ignition timing procedure
must be followed.
7.Release distributor clamp and remove
distributor.
Page 826 of 873

86ELECTRICAL
6
REPAIR Refit
NOTE: If a new distributor is being fitted,
mark body in same relative position as
distributor removed.
8.Leads for distributor cap should be connected as
illustrated.
Figures 1 to 8 inclusive indicate plug lead
numbers.
RH-Right hand side of engine, when viewed
from rear.
LH-Left hand side of engine, when viewed from
rear.
9.If engine has not been turned while distributor
has been removed, carry out instructions 10. to
17. Alternatively proceed to instruction 18.
10.Fit new 'O' ring seal to distributor housing.
11.Turn distributor drive until centre line of rotor arm
is 30Ê anti-clockwise from mark made on top
edge of distributor body.
12.Fit distributor in accordance with alignment
markings.
NOTE: It may be necessary to align oil
pump drive shaft to enable distributor
drive shaft to engage in slot.
13.Fit clamp and bolt. Secure distributor in exact
original position.
14.Connect vacuum hose to distributor and low
tension lead to coil.
15.Fit distributor cap.
16.Reconnect battery.
17.Using suitable electronic equipment, set ignition
timing.
See Adjustment, Ignition timing
18.If engine has been turned with distributor
removed, carry out instructions 19 to 30.
19.Set engine-No. 1 piston to static ignition timing
figure
See ENGINE TUNING DATA,
Information, Engine 3.9 V8i
20.Turn distributor drive until rotor arm is
approximately 30Ê anti-clockwise from number
one sparking plug lead position on cap.
21.Fit distributor to engine.
22.Check that centre line of rotor arm is now in line
with number one sparking plug lead on cap.
Reposition distributor if necessary.
23.If distributor does not seat correctly in front
cover, oil pump drive is not engaged. Engage by
lightly pressing down distributor while turning
engine.
24.Fit clamp and bolt, do not tighten.
25.Set ignition timing statically to 6Ê B.T.D.C.
26.Connect vacuum hose to distributor.
27.Fit low tension lead to coil.
28.Fit distributor cap.
29.Reconnect battery.
30.Using suitable electronic equipment set the
ignition timing.
See Adjustment, Ignition
timing