Onan NHM Series User Manual

Ignition Module Test
1. ~emo~e both spark plug cables from the igni-
tion
c01l so that the engine cannot start when
the crankshaft
is manually rotated.
IAWARNINGI Severe persontll injury or death
can
result if the engine starts while manual-
ly rotating the crankshaft. To prevent start-
ing during this test, remove both spark plug
cables from the ignition coil.
2. Connect the positive ( +) side of a voltmeter to
the negative
(-) terminal of the ignition coil
(larger of the two screw terminals} and the
negative
(-) side of the voltmeter to engine
ground.
3. Remove ali leads from the positive(+) terminal
of the coil.
4. ~sea jumper to connect the red lead of the igni-
tion module (the one just removed from the
coil) to the battery positive(+) terminal.
5. Rotate the engine clockwise using a socket
head wrench (either a 3/8 inch Allen orTorx)
on
the generator through bolt. Replace the ignition
module
if voltage does not jump from approxi-
mately
1 volt to approximately 12 volts, and
then back again, each revolution.
Ignition Coil Test
1. Remove all wires attached to the ignition coil.
2. Remove the coil from the engine.
3. Inspect the terminals for corrosion, looseness,
cracks or other damage. Look for carbon run-
6-12
ners around the high tension terminals: these
indicate electrical leakage. Replace a dam-
aged or leaking coil.
4. Clean the outside of the coil with a cloth damp-
ened
in parts cleaning solvent.
5. Measure primary coil resistance (across the
positive[+] and negative[-] terminals). Replace
the ignition coil
if primary resistance is not be-
tween
3 and 5 ohms.
6. Measure secondary coil resistance (across the
~park ~l~g cable terminals). Replace the igni-
tion cotl1f secondary resistance
is not between
14,000 and 30,000 ohms. See Figure 6-8.
FIGURE 6-8. TESTING THE IGNITION COIL

Onan NHM Series Specifications

General

Brand	Onan
Model	NHM Series
Category	Inverter
Language	English