Generac Power Systems NP-40G - Manual (Page 93)

Section 6.4- ENGINE IGNITION SYSTEM
Ignition Module (Continued)
Ignition Coii
Primary Ignition voltage (12 VDC) Is delivered
from the Ignition Module to the Ignition Coll. The
Coil boosts the voltage and delivers the high volt­
age to the engine Spark Plug.
Spark Piug
The Spark Plug on GN-190 and GN-220 engines
is a Champion RC12YC (or equivalent).
Clean the Spark Plug and reset its gap to 0.030
inch (0.76mm) every 100 hours of operation. Clean
by scraping or wire brushinq and washing with
commerciaf solvent. DO NOT blast clean the spark
plug.
Summary of Operation
See Figure 6. As the generator’s permanent mag­
net rotor turns, magnets in the Rotor hub’s Ignition
Cage rotate past an Ignition Sensor at fixeci inter­
vals.
Battery voltage is delivered to an Ignition Module
during cranking and running, via Wire 14. From the
Ignition Module, battery voltag^e is also delivered to
the Ignition Sensor via the RED (+) lead. The Igni­
tion Sensor acts as a "trigger" mechanism, causing
the Ignition Module to deliver its output to the
Ignition Coll at timed intervals. Current flows
through the primary coll of the Ignition Coil and
then collapses to Induce a high voltage Into the
Ignition Coil’s secondary coil. This high voltage
(about 25,000 volts) is delivered to the Spark Plug
to fire the spark plug gap.
Components encapsulated in the Ignition Mod­
ule provide an automatic spark advance. At crank­
ing speeds, ignition will occur at about 15'-18*
BTDC. At higher speeds. Ignition can occur up to
29* BTDC.
Ignition Timing
Ignition timing is fixed and non-adjustable.
Testing the System
GENERAL:
Solid state components Inside the Ignition Sen­
sor, Ignition Module and Ignition Coil are not acces­
sible and cannot be serviced. If any of these com­
ponents is defective, the entire component must
be replaced. The system does not include an arma­
ture and there Is no air gap to adjust, or breaker
points to adjust or replace.
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