M.T.H. RailKing RKS SD70ACE Quick start guide

M.T.H. HO
SD70ACe/SD70M-2
Diesel Engine
Congratulations! You've just purchased the most
technically advanced HO diesel locomotive ever
produced! This highly detailed model includes a
broader range of features than you’ll find on any
other HO scale diesel, including operating
flashing ditch lights; smooth performance from a
12-Volt 5-Pole Precision Flywheel Equipped
Skew-wound motor; and a DCC-Ready plug-in
receptacle for any DCC receiver. If you’re
looking for modern motive power that’s
accurately detailed, smooth running, and a great
deal of fun to operate, it doesn’t get any better
than this.
PLEASE READ THE MANUAL BEFORE USE AND SAVE
WWW.MTHHOTRAINS.COM
DCC Ready
ENGINEER’S GUIDE

TABLE OF CONTENTS
UNPACKING YOUR ENGINE 4
Removing and Unwrapping Your Engine 4
What Else is in the Box? 4
PRODUCT OVERVIEW 5
Getting to Know Your Engine 5
Engine Diagram 6
Removing the Body 6
SET-UP 9
Lubrication 9
FEATURES AND OPERATION 9
Analog DC (standard DC power pack) 10
DCC Digital Command Control 10
Installing your DCC Decoder 12
SPECIFICATIONS 14
CARE AND MAINTENANCE 15
Troubleshooting Guide 15
HOW TO ORDER PARTS 16
SERVICE & WARRANTY INFORMATION 18
Alternate Lighting Supply Jumper 11
Service & Warranty Information 18
Limited One-Year Warranty 18
This product may be protected by one or more of the following patents: 6,019,289;
6,280,278; 6,281,606; 6,291,263; 6,457,681; 6,491,263; 6,604,641; 6,619,594; 6,624,537;
6,655,640.
©2010, M.T.H. Electric Trains®, Columbia, MD 21046
CAUTION: ELECTRICALLY OPERATED PRODUCT:
WARNING: When using electrical products, basic safety precautions should be observed, including the following:
Read this manual thoroughly before using this device.
lM.T.H. recommends that all users and persons supervising use examine the hobby transformer and other electronic equipment
periodically for conditions that may result in the risk of fire, electric shock, or injury to persons, such as damage to the primary cord,
plug blades, housing, output jacks or other parts. In the event such conditions exist, the train set should not be used until properly
repaired.
lDo not operate your layout unattended. Obstructed accessories or stalled trains may overheat, resulting in damage to your layout.
lThis train set is intended for indoor use. Do not use if water is present. Serious injury or fatality may result.
lDo not operate the hobby transformer with damaged cord, plug, switches, buttons or case.
Recommended for Ages 14 and up. Not recommended for children under 14 years of age without adult supervision. As
with all electric products, precautions should be observed during handling and use to prevent electric shock.

M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
3
QUICK START GUIDE
I USE A REGULAR DC SUPPLY…
Step 1: Unpack your Engine (refer to unpacking instruction on pg 4)…
Step 2: Set the engine on the track …
Step 3: Apply increasing DC voltage until she starts up and pulls out!
CAUTION: M.T.H. HO engines DO NOT OPERATE ON AC
VOLTAGE. Applying AC power to your locomotive could cause permanent
damage and will void your warranty.
Of course, you should read your manual over before running your engine,
but if you just can’t wait you’re in luck. Your MTH DCC Ready engine is
ready to run out of the box. Follow the three simple steps below to get
your new engine up and running. Now, after a few minutes, shut her down
and read through your engineer’s guide.
.

UNPACKING YOUR ENGINE
Removing and Unwrapping Your Engine
Carefully remove and unwrap the model on a soft surface. By nature, models
with high levels of detail have some small fragile parts.
Carefully remove any foam packing pieces that may be surrounding the model.
What Else is in the Box?
The following items are packed with your engine.
Engineer's Guide (1)
You probably know that since you're reading it.
ALT-L Pad Jumper (1)
This is for the ALT-L pad on the MTH DCC Ready Engine Board
M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
4

PRODUCT OVERVIEW
Getting to Know Your M.T.H. HO Locomotive
Key Features
Your new HO Diesel Engine is equipped with a DCC-Ready receiver receptacle.
In plain English, this means your locomotive is ready-to-run using any DC power
supply and can be quickly updated to command control with any DCC decoder.
Compatibility
This HO model has directionally controlled LED's, has locations for DCC
decoders to drive the Number boards and Ditch Left and Ditch Right LED's
(extra F functions on applicable DCC decoders).
Compatible with any DC power supply
Compatible with DCC decoders that use the standard 8-pin NMRA connection
M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
5
Lights
As you read on, you'll notice there are no instructions for replacing light bulbs in
your diesel. That's because there aren't any. We use specially designed and
controlled LEDs to create realistic lighting effects that occur automatically. All
the lights for this model are LED’S (headlight, two number boards, two ditch
lights and a tailight) Again, NO PROGRAMMING!!
More…
No other HO locomotive has features like these. There are so many more things
to learn and enjoy about M.T.H. HO Engines, we could write a book. But, that's
no fun. So, if you haven't already done so, flip to the Quick Start Guide and let's
run your new engine!!

ENGINE DIAGRAM
Locomotive
M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
6
GPS Receiver
Metal See-Through Fan Vents
Detailed Horn
Magnetic Kadee®
Compatible Couplers
Detachable Snow Plow
Crew Figures
Die-Cast Air Tanks and Fuel Tank
Warning Placards
Safety Tread on End Steps
All wheels Powered
Removing the Body
Follow the below steps to remove the body and access the DCC ready control
tabs. You will need to remove 4
First remove the two in the front of the engine.
handrails.
handrails Use tweezers or
needle-nose pliers to carefully pull the handrail from the body. To prevent
damaging the paint wrap the pliers or tweezer tips in masking tape.
Remove
Handrail
Remove
Handrail

M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
7
To access the front and rear body tabs you must first remove the
truck bottom plate and wheel sets. To do this:
1. Remove the truck bottom plate using a thin-bladed screwdriver. Once removed
note the orientation of the bottom plate. It only goes back on one way. The end
that has the angle cut into it goes towards the fuel tank
2. Using tweezers or needle-nose pliers, gently pull both truck sides outward to
release them from the wheels. NOTE - The pick-up wires are attached to the truck sides
so take care not to pull them out too far or the pick-up wires could be damaged
3. Lift all three wheel sets up. Note the gear location on each wheel set so they
can be re-installed correctly
Then remove the handrails on the left and right side front of the engine. You can
either remove the stanchions from the body or pop the handrail off the
stanchions. Use tweezers or needle-nose pliers to carefully perform this. To
prevent damaging the paint wrap the pliers or tweezer tips in masking tape. Take
care not to deform the handrail or break the handrail stanchions.

M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
8
4. Using a small-bladed screwdriver gently push the tabs outward to release them
from the chassis
5. Now that you have the body tabs released gently lift the body away from the
chassis
6. Re-install the wheels sets into the front and rear trucks ensuring the gears mesh
7. push the truck side back over the wheels axles making sure each axle is in their
respective bearing
8. Snap the truck bottom plate back into place. NOTE - The truck side MUST BE
seated all the way towards the center of the truck because the truck bottom plate holds the truck
sides in place
9. Check that your truck sides are parallel to one another and that each wheel set
axle is seated in the bearing in the truck side. If one of the truck sides isn't
parallel then remove the truck bottom plate and ensure the truck side is pushed all
the way towards center and re-install the truck bottom plate. Again, the truck
bottom plate's angled end goes towards the fuel tank.
To re-install the body:
1. Slide the body over the chassis taking care not to catch it on the handrails you
removed earlier
2. Press down evenly on the front and rear of the top of the body to engage the
clips onto the chassis
3. If you have the body clipped to the chassis correctly you should be able to pick
the model up by the body
4. Re-install the handrails you removed earlier
Tab
Tab

M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
9
Lubrication
Using light machine or household oil, apply a very small amount to all axles
points as shown.
Your gearbox is properly greased at the factory and probably never needs service
however, if you run excessive hours pulling heavy loads, it's a good idea to
remove the 2 screws from the gearbox cover and re-grease using M.T.H. gear
grease or equivalent.
Lubricate Axles (L)
SET-UP
Lubricate Axles (L)
FEATURES AND OPERATION
Now, for the fun stuff! Your new M.T.H. HO Diesel Engine has more features
and operating capabilities than any HO engine ever built by any manufacturer.
We're going to walk you through everything she does in general but, you'll
probably find a few we forgot to mention on your own.
Don’t worry. We’ve taken care of the hard part for you. Your MTH DCC Ready
engine already has the jumpers installed at the factory so all you have to do is set
it on the rails, apply DC power and away you go.
Conventional Operation Jumpers
Your MTH DCC Ready engine has pre-installed jumpers that allow for out-of-
the-box operation. However, you can remove these jumpers to change the
lighting to your liking. You can shut off the Ditch Lights or the Number Board
Lights by removing the jumpers on the engine's circuit board. Please refer to
Removing Jumpers in the DCC Operation section of this manual.
It is important to note that there two sets of jumpers that route track power to
your engine's motor. These must be installed when operating in Conventional DC
mode.
Couplers
MTH DCC Ready engine comes with Kadee-compatible couplers already
installed.

M.T.H. HO SD70ACe & SD70M-2 Diesel Engine
10
FEATURES AND OPERATION
Modes of Operation
Analog DC
This is when there is nothing connected to the rails except a conventional DC
power pack. These power packs generally have at least one variable output
controlled by a throttle of some sort and a means of reversing DC polarity on
the track to change the direction of your engine.
DCC
The user connects their DCC decoder of choice to the MTH DCC Ready
board's 8-pin header following the DCC decoder's manufacturer's instructions.
Analog DC
Not much explanation is required here, and that's exactly why you run your trains
this way! Here's the good news, even if you like to keep it simple, your MTH HO
engine is outfitted with lights, features, that you're going to love.
Running the Engine
Set the engine on the rails, and apply DC power. Refer to the Set-Up section of
this guide for instructions on how to lubricate the chassis.
As you increase power, at about 3 volts, the lights will come on and she'll move
out!
Changing Direction
Lighting
Continue increasing the voltage all the way to 16 volts DC for maximum
speed.
Reduce the throttle until the engine stops, flip the direction switch, and then
increase the throttle again.
Your model is equipped with a headlight, operating ditch lights, and number
board lights. In analog DC mode, lighting operation is fully automatic.