Onan NH User Manual

Ignition and Battery Charging
IGNITION TIMING
.016 inch (0.41 mm) by adiusting the socket head
Timing
is preset atthefactory.Slighttiming changescan
be made by adjusting the points.
screw
(D) inward or.o&.va;d (Fighe 28). Make sure
feeler gauge is clean and free of any grease, oil, or
dirt.
A .016 inch point gap is equivalent to 20' BTC.
The engine is equipped with an automatic type battery
ignition system. Both spark plugs fire simultaneously,
thus the need for a distributor is eliminated.
7. Replace breaker box cover, coil wire, spark plugs,
and spark plug cables.
-
BREAKER POINTS
The timing is adjusted during initial engine assembly
and is fixed by the point gap adjustment. To maintain
maximum engine efficiency, change the breaker
points every 200 hours of operation.
Replacement and Adjustment
1. Remove spark plugs.
2. Remove breaker box cover. Rotate crankshaft
clockwise (facing flywheel) until points are fully
open.
3. Remove condenser (screw A) and detach con-
denser lead and coil lead screw (screw
B). See
Figure 28.
4. Remove two Allen screws (C) and lift breaker
assembly from engine.
5. Replace condenser and point assembly with new
parts and reinstall, using above procedure in
reverse order
of removal.
6. Adjust point gap by rotating crankshaft clockwise
(facing flywheel) by hand until the pointsarefully
open.
Set the point gap (using flat feeler gauge) at
Continuity Test
As a check for proper ignition timing a continuitytest
may be performed:
1. Adjust breaker points.
2. Remove air intake hose or cylinder shroud to
expose timing marks (Figure 29).
3. Rotate flywheel clockwise until timing mark is
aligned with the mark corresponding to 20" BTC
on top of gearcase cover.
4. Connect an ohmmeter or a continuity test lamp
set across the ignition breaker points. Touch one
test prod to thecoil lead terminal (screw
B Figure
28).
5. Touch theothertest prod toagood ground on the
engine.
6. Turn crankshaft against rotation (counterclock-
wise) until the points close. Then slowly turn the
crankshaft with rotation (clockwise).
7. The lamp should go out (continuity lost) just as
the points break, which is where ignition occurs.
If timing is early (advanced), the point gap is too
large. If timing is late (retarded), the point gap
is
too small. Adjust point gap accordingly.
n POINTGAP. !I
FIGURE 28. SETTING POINT GAP
28

Onan NH Specifications

General

Brand	Onan
Model	NH
Category	Engine
Language	English