Gas Engine Technology

Section 9 - Ignition System Fundamentals

Lesson Topics

• Functional role of ignition system

• Evolution of Waukesha systems
• Discuss the system components
• Features/function
• Variables
• Maintenance
• Ignition system troubleshooting
Ignition System - Purpose

The objective is to ignite the mixture…

To do that it must:
• Create a high voltage
• Distribute that voltage at the correct time
• Convert that voltage to a spark for a “controlled burn”
Type of Ignition Systems

Waukesha Ignition Systems are all based on the

“Capacitive Discharge” process
What type of ignition systems do you have experience with?
• Magneto
• CEC
• ESM
• ESM2
Waukesha Ignition Systems

The primary goal is to ignite the air fuel mixture

Pre-1993 1993 2000 2017

Magneto CEC ESM ESM2
Spark Plugs
Functional Requirements

The objective is to…

• Reliably spark under varying conditions
— engine load, speed, fuel, etc.
• Perform safely in harsh environments
• Fire at the right time in relationship with piston position
(Timing)
Plug Construction
Terminal Stud

Ribs
Sillment Seal

Shell
Insulator
Seal Washer

Threads (Reach)
Center Electrode
Ground wire
Plug Heat Range

Cold Hot
Temperature vs. Load

Cº Fº
1357/ 2500

1082/ 2000
Temp

807 / 1500

532 / 1000

257 / 500 Low High

Engine Load
 INNIO Waukesha’s Precious Metal, Long Life Plugs

• P/N 69919D spark plug

for lean burn engines.
• Precious metal and
cross-cut design provide
extended spark plug life.
• Operating temperature of
GSI engines does not
allow the use of these
spark plugs or other
precious metal type spark
plugs.
IPM-D2 / Spark Plugs

• Targets 4k hour life with non-precious

metal plugs
• Benefits new timing map…compared
to previous map on ESM & ESM2 which
used IMP (load) & speed
• New system accounts for WKI
• Specific IPM-D2 for Series 5
 VHP Spark Plugs

Engine Electrode
S5 4-ground non-
precious metal
S4 G/GSI J-type non-precious
metal (60999 series)

GL/LT J-type precious

metal (69919D)

S5 S4 GL/LT
 Factors That Raise Firing Voltage

• Cold Operating Temperatures

• High Compression Ratios
• Engine Load
• Wide Electrode Gap
• Rounded Electrodes
• Deposits
• Reverse Polarity
• CO2 In The Fuel Gas
The Story a
Spark Plug Tells
High Ash Buildup

Is this cylinder firing?

This spark plug has an

obvious high ash build-up
• High Ash Oil
• Poor Oil Control
Excessive Temperature, Melted Electrodes

• The firing tips on these plugs

have been destroyed by
excessive temperature.
• Under torqued spark plugs
have poor heat transfer and
thus excessive temperature.
Gap Bridging

Fuel particulates can

cause problems

Bridging Deposits
What Do You Think Caused This Wear?
Side Electrode Erosion

Is erosion on side
electrodes normal?
Checking Ground Connections

Checking the coil

ground wiring
Plug Tip Condition

This represents a normal-looking

used RM77N with normal wear
patterns
Aluminum Contamination

Detonation
Oil Fouled Tip

Is this cylinder firing when

wet looking oil deposits
like this show up?

See latest Service Bulletin

SB 16-2864
 Stretched Threads

Both spark plugs have anti-seize applied to the

threads, the spark plug on top has three
problems as a result.
1. Contamination of the firing electrodes
causing misfire.
2. Excess clamp load causing the electrode gap
and firing voltage to increase
3. Excess clamp load has caused the spark
plug shell distortion and broken sillment
seal (bond between steel and ceramic).

Torque spark plugs dry unless the specification

states differently.
Torquing Wet vs. Dry
DRY
K- factor / Friction
WET

Seat Load 3000 1360kg/m)

 Spark Plug Troubleshooting

Table 17.00-2

If any of these
conditions exist,
be sure correct
the cause before
installing new
spark plugs
Ignition Coils
 Engine Mounted Ignition Coils

Engine mounted coils were

the standard for years and
are still available on some
Waukesha engines
 Spark Plug Wire and Extension

Engine mounted coils have a high voltage

wire that was susceptible to breakdown and
wear which could lead to misfires and arching
CD(2

Flange Mounted Ignition Coil

Provided on all new and re-

man Waukesha engines

Mounting and grounding

flange meets CSA Class 1
Division 2 hazardous
locations
Coil O-Ring seals out moisture
while maintaining CSA
requirement
Slide 31

CD(2 Callies, Douglas (INNIO), 3/8/2022

Ignition Coil with Integrated Wire
Old style required additional
manual connections New style has integrated coil wire
Spark Plug Extensions

(Original design shown)

Spark Plug Extensions

Updated Design
 Servicing Ignition Components

• Clean oil and grease from extensions

• Use Krytox high temperature dielectric
grease on the “O” rings and silicone boots
• Use the appropriate puller tool P/N 475075
for removing extensions from spark plugs.
 Cleaning High Tension Components

CD(1

It is very important to
clean the secondary
coil connection
Slide 36

CD(1 new middle picture better showing contamination

Callies, Douglas (INNIO), 5/19/2021
ESM and ESM2
Engine Control Units

• ESM and ESM2 are integrated control units

• They takes the things learned in CEC and the related add on
modules (DSM, TCM, KDM, TCM2, AFM) and puts them into one
control system
 Controls Evolution-Engine System Manager (ESM)
Introduced 2001

CEC ESM

Replaced
IM TCM By
+ +

DSM
AFM
Governor Customer Start-
CEC-IM, DSM, TCM, AFM
Stop, Shutdowns

ESM replaces functions of all CEC modules, governor, and customer

control of start-stop functions and alarm and shutdowns
 Controls Evolution-ESM2 Introduced 2018

ESM2
ESM
275GL+
+ = NOx Control Replaced
+ NCM 5 Button HMI By
VGF SE
ECU + = VHP S4 GSI ECU
AFR2 Control
8 Button HMI
ECM

HMI
 Control System Summary-Page 1
Feature Magneto CEC ESM ESM2
Fixed Spark X
2 position spark IM
Knock Sensing and Control DSM X X
Wastegate and bypass Control TCM X X
Air/Fuel Ratio Control AFM X X
2 D Mapped spark X
WKI Spark Adjustment X X
Spark Plug Condition Monitoring X X
PID Governor Control X X
Nox Control NCM X
Catalyst Feedback Air/Fuel Ratio Control ECM X
Engine Autostart Control X X
 Control System Summary-Page 2
Feature Magneto CEC ESM ESM2
Alarm and Shutdown Control X X
Fault Logging X X
Ability to Log Operation X X
Modbus Data Output X X
E-help X X
3D Mapped Spark X
Multi-strike Ignition Capability X
Misfire Detection X
Model Based Governor Control X
Continuous Operation Logging X
Exhaust and Main Bearing Temperature Readout X
Operation Graphing X
ESM/ESM2 Theory of Operation

-D

ECU Central “Brain” – IPM-D Provides Voltage Preprogrammed

Factory Information, Engine Speed, Intake Manifold Pressure, & WKI
Detonation Sensing
Ignition Power Module w/Diagnostics

• ESM Component

• The IPM-D is needed to

fire the sparkplugs at the
required voltage

• IPMD-2 provides multi-

strike capability for
operating conditions that
are difficult to ignite.
As represented on ESM
Camshaft Magnetic Pickup

VHP Vee located in valley

VGF- between heads
SE
Engine Control Units

• The ECU’s have internal maps that determine when the

sparkplugs will fire
• There are no serviceable parts inside the box
 Cam Gear Magnetic Pickup

Gear mounted timing disk

Flywheel Magnetic Pickup

flywheel holes
Knock / Detonation Sensors

CEC Knock
Sensor

ESM/ESM2
Knock Sensor
ESM Detonation Detection Theory

• Monitors each combustion

event in a “Window”
• Compares Knock Levels
• Responds Proportionally
• Monitors Above 50% Load
• Self-Calibrating
• Records In Fault Log
Spark Timing Control: Knock protection
• Displays On PC system alters timing to prevent eliminate
detected knock
Ignition
Troubleshooting
Check Your Ground

• Make sure that connections are

clean & tight

• Ground connections are often

overlooked
 Grounding

• AC: Ground is a safety path

• AC or DC: ground provides a 0-volt
reference
• Our DC systems: Crankcase DC Pwr + - ESM2
ground is the 0-volt reference for Battery
all engine systems. All control
connections must have a common
ground, the crankcase. Crankcase
• The crankcase should also be tied
to true earth ground (changes Earth
floating ground to earth ground)
Power Supplies

• Alternator Power Supply

• 24-volt, 50 Amp

• Available with option code

Shown with the guards removed

 Batteries are Highly Recommended

• Battery provides
backup power to run
engine during brief
outages
• Battery acts as a filter
for DC power
• #6 AWG for up to 25 ft
of round-trip wiring
between alternator
junction box and
battery
Determining State of Charge

NOTE:
• Must be fully charged
• Remove surface charge before VOLTAGE STATE OF
testing CHARGE
o Apply 20 amps for 3+ minutes 12.7 & ABOVE 100%

• Measure open-circuit voltage 12.5 75%

12.3 50%
• Determine state of charge from
table 12.1 25%
11.90 & below Discharged
Check Wiring System

• Corded connections

• Broken or worn wires

• Loose pins or sockets

 Checking Wiring Harness Continuity

Use E-help and a

Digital Multimeter to
check continuity.

i.e. magneto
Questions
Answers

All rights reserved

 Legacy Training
Magnetos and CEC

Slides 66 through 92 are optional training for CEC and

magnetos. No homework or test questions will come from this
material.
Revision History
Date Author Change Detail
2016-02-16 Wauk Historic Draft
2016-09-02 Wauk Content update, re-organization
2017-01-01 Wauk Format incl. HmWk (+ Revision History pg.) + section title slides, +updated PAGE
Collaboration Header and footer, Feedback Watt Calls

2017-03-01 KH/CDJ Slide Master, Section #, Lrg. Redline re-org., removed slides, Sp. Translation,
Transitions
2017-04-20 KH +22, -85
2017-09-01 KH Rev. Release, footer updated, moved Rev. History to end.
2018-01-22 KH/MW Correct typo – notes pages 34 & 43
2019-05-15 RH INNIO template and colors. Removed GE logo.
2021-06-10 GWS Move white box on slide 76. Slide 18 change “dirty fuel” to “particulates”. Added
notes to Slide 5 “Waukesha Ignition Systems”. Added slide 12 S5 spark plug and
updated slide 13 updated spark plug from 69919 to 69919. Slide 35 removed GE
logo. Updated slide 68 models. Hid magneto slides and moved to end of
presentation. Slide 82 updated picture.
4-13-2023 GWS New or changes to slides 5, 11,13, 17,18, 20, 24, 26, 27, 28, 32,35, 36, 44, 45,
48, 49, 50, 54, 55, 56, 57, 58, 59
 Ignition System Comparison

Magneto Inductive Discharge Capacitive

• No external power source • Needs external power source • Needs external power source
• Magnets rotate around wire • Coil get power and creates • Power supplied to a transformer
(coil) to create primary primary charge in the ignition module to raise
charge voltage
• Charge is released by opening
• Primary charge sent to coils and closing of breaker or switch • Voltage (primary) is then sent to
for secondary charge that forces the primary charge to the charging circuit to charge the
the secondary windings. capacitor.
• Secondary coil charge sent
through high tension (HT) • Secondary charge sent to a • Charge in the capacitor is sent
leads (spark plug wires and distributor and sent down high out when the trigger circuit stops
extensions) tension (HT) leads (spark plug the charging circuit for rapid
wires and extensions) discharge
• HT leads connect to spark
plug to ignite the fuel mixture • HT leads connect to spark plug • Trigger signal sent to coil with is
to ignite the fuel mixture mounted on the spark extension
Magnetos
Magneto Theory of Operation

• Magneto combines distributor and generator

• Rotating magnets (primary and secondary windings)
• No longer used on current production
Magneto Components
Magneto components
Magneto Maintenance
Magneto Drive Discs

Previous
magneto
drive disc

Current floating
drive disc
CEC Ignition Control
CEC
CEC Ignition Module

Manufactured by Altronic®
exclusively for Waukesha Engine
• Digital
• Microcircuit based
• No moving parts
• Requires no maintenance
 CEC Ignition Module

Timing Switch
Covers
Application Switch
DSM
Connection
“D” Lead, Pick-up, Power
Connection & more
Connection for
coils and “G” lead
 CEC Ignition Module Timing Disc
Hall Effect Pickup

Timing Disc

VGF inline VHP vee

CEC Ignition

Module Operation Power Requirements Operating Voltage

• Approximately 160 • 24 Volt Nominal DC Starting: 10 Volts

VDC output Power Supply DC Minimum
• Aluminum timing • 2 Amp Continuous Running: 24 volt
disc operates at • Wiring must be nominal
one half engine sized for 30 (32 Maximum)
speed amperes DC
Installation Recommendations

• Two 10 amp fuses (optional)

• Maximum of 15 feet (450 cm) from
farthest coil
• Install using rubber isolators
• Maximum 150° F (65° C) case
temperature
• Case must have a separate ground
CEC Ignition Module

Ignition modules external selector switch

CEC Ignition Module

Interfaces with the Detonation Sensing Module

14 pin interface connection

for the DSM
(May or may not have connection)
Detonation Sensing Module (DSM)

Knock Sensor
 Timing Switch Adjustment

Red Dots
• Each stop (indent) on the timing
switches equals one degree of
timing change
• Position “0” to “15” equals
15 degrees of timing
change per switch
 D Lead in Power Distribution Box (PDB)
Active “D” Lead
Switch Status
A Grounded
B Open

Two (2) timing switches

on side of module
Timing CEC Ignition Module to Engine

i.e. VGF.
CEC Ignition Module Timing Disc

Hall Effect Pickup

Current production
Timing Disc
Gap for Pickup

AT25 VHP VGF back out the Hall effect pickup

counter-clockwise 3/4 turn from disc contact

AT27s back out the Hall effect

pickup 1 turn from disc contact

X
6 Cylinder VHP Timing Disc

#1 Cylinder

Pickup

X
Index Magnet

#4 Cylinder
 Timing

What is the timing for

this engine if the WKI
number is 84 & it’s
operating at 1200 RPM?

18° BTDC
Testing with an Ohmmeter

Disconnect the power supply from

the Ignition module before
attempting these ohmmeter tests
CEC Ignition Tester
 Hall Effect Pickup Testing off Engine Ohmmeter

+ -
1. Set ohmmeter to R x 10,000
2. Connect ohmmeter + lead to pin “A” &
-MEGA+
Volt
- lead to pin “C”
3. Connect to positive lead of an 8–12-volt power C
A
supply to the “B” pin & the negative lead to the B
“C” pin
4. Observe readings while pickup is moved in front
of a magnet
5. If meter reads infinite ohms (no deflection) with
magnet in place, replace the pickup