JLO L/RM252 - Assembly group 3; Timing Procedure

Assembly group 3
PROCEDURE
Special JLO Tools
Timing gauge
(1) 441.31.875.000
Timing light (2) 000.15.330.000
TIMING DATA:
- Engine Model L/RM 252 -
Timing BTDC .110 - .126 inches (2.8 - 3.2 mm)
Breaker Point Gap .012 - .016 inches (0.3 - 0.4 mm)
Spark plug gap .020 inches (0.5 mm)
PREPARATIONS
3.1. 1 Screw timing gauge (1) into spark plug hole of cylinder head.
2 Connect one lead of timing light to engine ground, the other lead to
the disconnected wire of the ignition system.
3 Bring piston into top dead center position.
BREAKER POINT GAP
4 Check breaker point gap with feeler gauge.
5 To adjust breaker point gap, loosen retaining screw
(4) and ad just to
specified gap by moving fixed part of point set (5).
6 Tighten retaining screw (4), and re-check gap.
IGNITION TIMING
NOTE
:
Breaker points must be adjusted to proper gap PRIOR to timing the engine.
7
8
9
10
11
Note reading
of timing gauge with the piston still in top dead center
position.
Turn crankshaft approx.
90° in opposite direction of normal direction
of rotation (away from TDC), then slowly turn flywheel towards TDC
until timing light (2) changes from dim to bright
or buzzer of timing
device changes loudness (timing point).
Note reading on timing gauge. The difference between the 2 readings
(step
7 and 9) is the timing in inches or mm, depending on calibration
of timing gauge, before TDC.
To change timing, loosen armature plate retaining screws (7) and rotate
plate in required direction.
NOTE
:
Rotating the armature plate in the direction of engine rotation will
retard the timing, while rotating the armature plate in the opposite
direction of engine rotation will advance the timing. Never attempt to
advance or retard the timing by changing the breaker point gap.
Tighten armature plate retaining screws (7), and re-check timing repea-
ting the procedure described in steps
7, 8, and 9.
NOTE :
If timing settings cannot be obtained, breaker points must be replaced.
If breaker points are corroded or otherwise contaminated, engine may
tend to backfire. Clean!
If breaker points are badly pitted, they must be replaced.
Replacement armature plates (12 Volts,
40 Watts) may be equipped with a
lighting coil. If coil is not used, it may either be removed prior to
installing the plate
or the 2 yellow leads may be cut off right at the
coil.
11