MTHTrains DL-109 DIESEL ENGINE User manual

R
ELECTRIC TRAINS
MTH DL-109 DIESEL ENGINE
OPERATING INSTRUCTIONS
Thank you for purchasing the MTH Electric Trains DL-109 diesel
locomotive. This ¼” scale reproduction of the famous DL-109 locomotive
measures over 19” in length and weighs over 5 pounds. Despite its scale
size, the locomotive is capable of operating on O-42 3-rail track with any
compatible AC transformer (see the chart on page 31 for a complete list of
compatible transformers and wiring instructions) and is completely
compatible with most other 3-rail locomotives, rolling stock and
accessories.
The locomotive is equipped with several deluxe features that are simple
and fun to operate. Each feature is described among the following pages
which should be read before the engine is operated. For those of you who
can’t wait to get started, the Quick Start Basic Operating Instructions
found on Pages 3 and 4 should be read so that you understand the basics of
the operating system.

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DL-109 Operating Manual
Table Of Contents
QUICK START - BASIC OPERATION 3
ProtoSmoke® UNIT OPERATING INSTRUCTIONS 4
Proto-Sound® OPERATINGINSTRUCTIONS 5
DCRU® Reverse Unit Operation(All 3-Rail Models) 5
Horn Operation 6
Bell Operation 6
ProtoCoupler® Operation 7
Squeaking Brake Sounds 8
Tips On Using Squeaking Brakes Sounds 9
Passenger Station Sounds (PFA) 10
Quick Overview On Activating and Triggering PFA 12
Tips On Using The Passenger Station Sounds 15
Reverse Unit Lockout Control Functions 16
Locking The Engine Into Forward or Reverse 16
Unlocking The Engine 16
Self-Charging Battery Backup System 17
Replacing The Battery 17
Proto-Sound® Volume Adjustment 18
USING “RESET" TO PROGRAM Proto-Sound® 19
Remotely Setting The Engine Volume 19
ProgrammingForSqueakingBrake Operation 20
Programming For Horn In Neutral Operation 20
ProgrammingForProto-Coupler® Operation 21
Turning Off Cab Chatter Sounds 21
Programming For PFA Operation 22
Activating Remote Lock-Out Control 22
Resetting All Proto-Sound® Options To Factory Defaults 23
OIL & LUBRICATION INSTRUCTIONS 24
TRACTION TIRE REPLACEMENT INSTRUCTIONS 25
LIGHT BULB REMOVAL & REPLACEMENT 26
TROUBLE SHOOTING PROTO-SOUND®PROBLEMS 27
Proto-Sound® RESET Feature Chart 30
Transformer Wiring Chart 31
O-42 OPERATION 32
SERVICE AND WARRANTY INFORMATION 36
HOW TO GET SERVICE 36
LIMITED ONE YEAR WARRANTY 36
WARNING:
When using electrical products, basic safety precautions should be followed including the
following:
-- Read this and all related manuals (transformer/power supply, locomotive, etc.) thoroughly
before using this device.
-- This device is not recommended for children under 8 years of age without adult supervision.
-- MTH recommends parents examine the toy transformer used to power this device periodically
for conditions that may result in the risk of fire, electric shock, or injury to persons, such as
damage to the primary or output cord, plug blades, housing or other parts (including proper
functioning of the circuit breaker), and that, in an event such conditions exist, the transformer
should not be used until properly repaired.

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DL-109 Operating Manual
QUICK START - BASIC OPERATION
The MTH DL-109 contains state-of-the art electronics with several built-in
automatic features for incredibly realistic operation. Despite these advanced
features, the DL-109 is easy to operate with any compatible standard AC
transformer (see the compatibility chart on page 31). All models are
equipped with an operating smoke system that should be primed with
smoke fluid before operating. Adding 20 - 25 drops of fluid through the
smoke stack should be sufficient. (See Figure 1a). If you choose to not
prime the smoke unit(s) with fluid, turn the smoke unit switch located
under the rear drive truck(s) to the
OFF position. (See Figure 1b).
This will prevent any damage from
occurring to the smoke unit when
the engine is running without a
primed smoke unit. For more
information see the section on Page
4 on smoke unit operation.
The DL-109 locomotive is
controlled by a ProtoSound®
DCRU® electronic reverse unit.
The reverse unit operates in the
same manner that all reverse units
function by using forward, neutral
and reverse states that are entered
each time the throttle is turned on
and off or by using the transformer
direction switch (if so equipped).
The reverse unit is designed to ignore dirty
track, dead spots on switches or minor
short circuits without disrupting the engine
operation, even at slow, prototypical
speeds. Once the engine is placed on the track, the throttle on the
transformer can be advanced. You will see that only the engine’s lights
come on and that only two dings of the ProtoSound bell occur followed by
the diesel start-up sounds (on ProtoSound equipped 3-rail models). The
engine does not run. This is known as the RESET (see fig 2) state and is
explained in more detail beginning on Page 5. The ProtoSound® DCRU®
will not power the motors until the throttle is turned OFF and then ON
ON OFF
Coupler
Direction
Switch
Smoke Unit
ON/OFF
Switch
Figure 1b: Locating The Smoke Unit &
ProtoCoupler®Selection Switch
RESET
Neutral
Reverse
Neutral
Forward
Figure 2: DCRU™ Cycle Phases
Add Smoke Fluid
Figure 1a: Adding Smoke Fluid to the Smoke Unit

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DL-109 Operating Manual
again. At this point, the engine will now function just like any other
electronic or mechanical E-unit.
PROTOSMOKE™ UNIT OPERATION
The DL-109 contains a self-powered smoke unit that outputs a steady stream of smoke
through the smoke stack on the roof of the engine. The ON/OFF switch located next to the
power truck must be in the ON position in order for the smoke unit to function. See Fig. 1b on
page 3.
The smoke unit is essentially a small heating element and wick which soaks up and then
“cooks" a mineral oil-based fluid that omits a harmless smoke. The smoke is then forced out
of the stack via a small electric fan which runs at a constant speed. However, the smoke
intensity can be varied by increasing the transformer voltage setting. The higher the setting,
the more intense the smoke output.
For best results, we recommend that you add 20 - 25 drops of ProtoSmoke™, Seuthe, LGB or
LVTS fluid before you run the engine. If you don’t choose to add the fluid, then the smoke
unit switch should be turned off. Failure to either add the fluid or turn the switch off could
lead to damage to the smoke unit heating element and or wicking. Add the fluid through the
smoke stack hole. After adding the fluid, gently blow into the stack to eliminate any air
bubbles. Do not overfill the unit as overfilling can cause the fluid to leak out and coat the
interior engine components. When the smoke output begins to diminish while running the
engine, an additional 20-25 drops of smoke fluid should be added or the smoke unit switch
should be turned off. When storing the engine for long periods of time, you may want to add at
least 20 drops of fluid to keep the wick soaked with fluid and prevent it from drying out. After
removing the engine from storage, it is
advisable to add another 25 drops of fluid,
letting the wick soak up the fluid for 15
minutes prior to operation.
SMOKE UNIT
MAINTENANCE
CAUTION: Operating the engine without
smoke fluid and with the smoke unit switch
in the ON position can damage your smoke
unit wick, causing the wick to become hard,
blackened and unabsorbant around the
heating element. When this occurs, it may
be difficult for the wick to soak up the
smoke fluid resulting in poor or no smoke
output. If that occurs, we recommend that
you inspect and/or replace the wick taking
care to not run the engine without fluid in
the future. You can inspect the wick to see
if it needs replacement by removing the
smoke unit circuit board from the smoke unit body as seen in Fig.3. After removing the circuit
board screws lift the circuit board away and inspect the wick. If the wick is darkly discolored
and hard, it should be replaced.
Smoke Unit
Circuit Board
Mounting Screws
After Removing
Mounting Screws,
Lift Circuit Board
To Reveal Wicking
Figure 3: Inspecting The Smoke Unit Wicking

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DL-109 Operating Manual
Proto-Sound® INSTRUCTIONS
The MTH Proto-Sound® digital sound and train control system provides
the operator with unprecedented realistic operation on your model railroad.
In addition to actual diesel engine, CD-equivalent 16-bit digital sounds,
you get the following features:
1. ∗Built-In DCRU® Reverse Unit * Authentic Diesel Engine Horn Sound *
Authentic Diesel Engine Bell Sound * Squeaking Brake Sound * Passenger
Station Sounds * Operating Remote Controlled ProtoCoupler™ *
Self-Charging Battery Back-Up System With Automatic Battery Shut-Off *
Remotely Controlled Reverse Unit Lock-Out * Remotely Adjustable Diesel
Engine Volume * Authentic Diesel Engine Start Up & Shut Down Sounds *
Each feature is described among the following pages. Though the system
is easy to use, we encourage you to read the instructions thoroughly.
Proto-Sound® DCRU® REVERSE UNIT
As mentioned in the Basic Operating section, the engine is controlled by a
Proto-Sound® DCRU® reverse unit that contains the standard
forward-neutral-reverse states found on most reverse units. However, as
described earlier, when power is first applied to the track, the reverse unit
begins in RESET or what seems like a neutral state. Power must be
interrupted again to get the locomotive to enter the forward state. It is this
first RESET state that gives Proto-Sound® its unique, remote controlled
functions. The system will enter RESET whenever power to the track is off
for three or more seconds. NEUTRAL will be referred to as the state
between Forward and Reverse.
Proto-Sound® is equipped with a microprocessor, that, depending on the
amount of memory it is allotted, allows the user to utilize several remotely
activated functions. In the simplest terms, Proto-Sound® has its own
“Computer" controlling these functions. In order to access many of these
remotely controlled functions, the user must be in the RESET state to do so.
RESET is entered anytime power to the locomotive has been off for more
than 3 to 5 seconds. When the engine first enters RESET, the
microprocessor initiates a system check to determine if the system,
transformer and engine are operating correctly. This takes approximately
2.2 seconds during which you will hear the engine’s startup sounds begin.
In order for ProtoSounds to properly initiate the system check, do not

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DL-109 Operating Manual
advance the transformer throttle past 10 volts when you first enter RESET,
wait for the diesel startup sounds to begin and then slowly turn the
transformer throttle to the off position and then back on again to enter the
forward phase. Interrupting the power too quickly may cause the system to
re-enter RESET (signaled by two dings of the bell). Should this happen,
wait longer before interrupting the power to enter the Forward phase.
Proto-Sound® comes with several programmable functions, including
Engine Volume Adjustment, Separate Bell Button Operation
(pre-programmed at the factory), Cab Chatter On/Off Control, ProtoCoupler
On/Off Control and Horn-In-Neutral Operation. Each of these features are
described in more detail later. You will notice that when in RESET, your
engine will not respond to the whistle button with a horn blast or continuous
bell ringing. In fact, when in RESET and the whistle button is depressed,
only one single bell chime will be heard each time the whistle button is
pressed. If you don’t want to configure or change your locomotive using
any of these programmable features, simply leave RESET and wait 2.2
seconds before interrupting the power to put the engine in forward. After
you leave RESET, your engine will operate normally in all the direction
states of forward, neutral and reverse.
HORN OPERATION
Your MTH DL-109 Proto-Sound®-equipped engine is equipped with a
digital recording of a diesel horn. The horn sound can be activated anytime
the engine is in forward or reverse by pressing the horn/whistle button on
your transformer. The horn will continue to blow as long as the
horn/whistle button is depressed. The horn will not function in RESET and
must be configured through a RESET option to allow the horn to work
when the engine is in neutral. See page 20 for information on horn
programming in the Using RESET To Program ProtoSounds®section of
this manual.
BELL OPERATION
Your Proto-Sound® equipped engine also features a digital recording of an
actual steam engine bell. The bell can be turned on or off by simply
pressing the Bell button on your transformer anytime the engine is in
forward, neutral or reverse. The bell will continue to ring until the bell
button is depressed a second time. Note: The bell will not function in
RESET.

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DL-109 Operating Manual
In fact, because of Proto-Sound® state-of-the-art design, the
microprocessor remembers its last command. Therefore, unless you turn
the bell off before you quit running your train, the next time you run the
engine, the bell will come on. No matter whether you come back an hour
later or a year later, the bell will begin chiming once the engine enters one
of the three directional states.
To turn the bell on using the transformer’s whistle button, turn on power to
the track and cycle the engine into NEUTRAL. Turn the throttle to 8 volts
or less (any higher voltage will arm the ProtoCoupler™) and press the
whistle button. The bell should begin chiming. To turn the bell off, press
the whistle button again. If you want to keep the bell on while running the
engine, simply interrupt the power with the transformer throttle or the
transformer directional switch and enter forward or reverse.
PROTO-COUPLER™ OPERATION
Your MTH DL-109 Proto-Sound®-equipped locomotive has two
coil-wound ProtoCouplers™ for remote uncoupling action. The couplers
are mounted on the power trucks. Because the ProtoCoupler™ is controlled
through a Proto-Sound® microprocessor, it doesn’t require an uncoupling
track section or modification to your layout to function. The three simple
steps below are required to operate the coupler.
1. Put your engine in NEUTRAL and turn the throttle all the way
up.
2. Press the transformer whistle button to “Arm" the coupler. (You
will hear a “Clank")
3. After arming the coupler, press the whistle button again to open
the coupler.
When the knuckle fires open you will hear the buzzing of the coil
energizing and the sound of the air lines coming apart. It can best be
described as a CHA-CHUSHHH sound. The coupler doesn’t have to be
fired in NEUTRAL. Once the
coupler is armed it can be fired
in Forward, Neutral or Reverse.
However, you may find that the
coupler doesn’t open when
firing the coupler at high
H H
Put Engine In Neutral
At Full Power
Press & Release
The Whistle Button Press & Release
The Whistle Button
Listen For The
Ca-Clunk Sound
See The Coupler Open
And Listen For The
Cha-Chusshh Sound

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DL-109 Operating Manual
speeds. Reduce the voltage setting on your transformer if this occurs and
run your engine at a slower speed before firing the coupler. If the coupler
continues to open erratically, try lubricating the knuckle with light oil as
indicated in Fig. 4.
For multiple heading purposes,
only one of the two
Proto-Couplers will function at
any one time. Use the coupler
direction switch as shown in
Fig. 1b on page 3 to select
either the front or rear coupler.
Simply slide the switch toward
the direction of the coupler you
want to make active.
Note: This scale DL-109 contains a three position switch. If the switch is moved to
the front of the engine, the front coupler will be selected. The switch moved to the
center selects the rear coupler. Moving the switch to the rear most location controls
the rear coupler on the separately purchased DL-110
NEUTRAL-ACTIVATED CAB CHATTER SOUNDS
Whenever your diesel locomotive is parked in Neutral, randomly played
“Cab Chatter” sound effects will occur every 2 to 30 seconds. There are a
total of four of these Cab Chatter sequences that capture authentic radio
transmissions between dispatcher and engineer. They are designed to play
at random intervals to eliminate repetitive and boring sequences though
there is no guarantee that you won’t hear the same message repeated two or
more times..
SQUEAKING BRAKE SOUNDS
Proto-Sound® equipped engines feature the ability to play the sound of
squeaking brakes whenever your engine slows in speed. There are two
settings for activating the squeaking brake sounds. The default setting
allows the brake sounds to play
while the engine is in forward or
reverse and the transformer
throttle is lowered from a high
setting to a low setting (14 volts
to 8 volts or less). The sound
oil coupler
knuckle
Figure 4: Lubricating The ProtoCoupler Knuckle
Throttle Down From
High Voltage To Low Listen For The
Squeaking Brake Sounds

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DL-109 Operating Manual
itself is a stored recording on the Proto-Sound® software chip and will
always play the same brake sound for the same three second length each
time the voltage is reduced from high to low. Some practice may be
required to synchronize the playing of the brake sounds with the movement
of the engine. It is not uncommon for the engine to stop before the brake
sound is completed. Operators will find that coordinating the movement of
the throttle setting from 8 volts to off will allow the engine to maintain its
movement while the brake sounds play. Note: The brake sounds will not
be heard if the transformer throttle is not set above 14 volts and/or not
reduced below 8 volts.
TIPS ON USING THE SQUEAKING BRAKE FEATURE
Users will find the squeaking brake feature to be a very
realistic way to simulate the sound of an engine slowing down
for curves, crossings or coming to a stop at a station, side track
or switch yard. However, you may find that your engine
continues to play the brake sounds once your engine comes to a
stop, or that the sounds stop before the engine comes to a
complete halt. For example, if you simply run the engine and
turn the throttle off quickly, the brake sounds will likely
continue playing even though the engine has come to a
complete stop.
This effect can be eliminated by simply practicing with the
brake feature. In no time, you will quickly learn how to
“feather" the throttle to keep the engine moving while the brake
sounds play and then turning the throttle off just as the sounds
stop.

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DL-109 Operating Manual
Operating Proto-Sound® Passenger Station
Sound Effects
Passenger Station Announcements (PFA)
Proto-Sound® is equipped with operator controlled Passenger Station
Sounds, referred to as PFA. The PFA sequence is designed to simulate
the arrival, disembarking, embarking and departure of a passenger train
in a Passenger Station. This easy-to-use feature allows you to play
digitally recorded sounds of Passenger Station sounds while your
engine is parked in the Neutral State. No additional wires or
modifications are needed to enjoy these amazing sound effects. The
sounds themselves are randomly “shuffled” by the Proto-Sound®
computer. This gives the system the ability to play the various sounds
in a different order each time PFA is enabled.
Activating Passenger Sounds -Quick Overview-
The following is a quick overview on how you can operate PFA.
The train on track moving Forward or Reverse direction.
B
Press and Hold Bell Button For 3+
Seconds, Listen For a Horn Blast or
Air Release, then Remove your Finger
from the Button.
BPress Bell Button Again Quickly to
Stop Bell Chime.
Your train is now ready for you to play the PFA.