I purchased a new MTH SD70ACE DCC ready diesel and turned it over to my friend who is a electrical engineer (retired) and an avid modelrailroader and installs decoders professionally. He installed a decoder that I had from TCS and upon running it for about 20 minutes it was cooked. He then installed another decoder and heres the message he sent me below.
I would remove the MTH main board and hard wire it. I hard wired my DCS version to a Tsunami.
Something in the Light board might be causing problems.
Also make sure the speakers are matched to the decoder. The loco has room for 2. You might have to wire them in series instead of parallel depending on their impedance.
Springfield PA
I have the same problem with the 2 MTH SD70ACe I have purchased. Last January at the West Springfield train show, the MTH reps told me it was a known problem and the motor must be replaced. I am still discussing with MTH since, but to no avail. I even offered to pay for the motors, still no reply yet.
I am the proud owner of two useless locos.
Jack W.
jaljoie, there has to be a whole lot of people out there with this problem, if they try to install a decoder for DCC use.
JB.
I know of another modelist that his loco came so hot, it distorted the shell. Maybe MTH is overwhelmed with returns and this is why I can't get a reply to my emails.
This is not all, a friend of mine bought 3 SD70ACe with Proto Sound 3 factory installed. Out of these 3 loco only 1 retain its cab address, The other 2 will lose programming by simply removing the loco from the track and store it for a short while.
At the Chicago MSI museum three of these MTH SD70ACe did not made the grade and had to be prematurely retired from the layout .
So much for MTH quality.
The motors they use are by Canon. I'm surprised they are having issues with them. Goes to show nothing's perfect.
I doubt very much it is the motor, those motors are VERY low current draw. It's their crazy wiring for the lighting. Half the current draw of my Stewart switchers with Canon motors is the headlight LED. I measured it running free and it was using just 25ma! I'd run out of slots on a DCS100 before I'd run out of the 5 amps available.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Randy, at first I suspected the lightboard but I did tested it with all light off with the same overheating results. I also tough about bind in the drive train but on DC the loco move steadily at 1.5 Volts.
On DC with a quality meter I could increase the amp drawing in excess of 1.7 Amp with wheels slipping.
I have 5 MTH SD70ACE / SD70M2 one is a sound unit,that one is ok so is 2 no sound.But the other 2 one went back to MTH for a motor replacement and when i git it back the other went bad,had them to send a replacement motor and about 30 min run time it went bad again.So no more MTH for me.
Russell
Wow, sure they are using actual Canon motors and not some knockoff lookalike? I can see issues like a drivetrain bind due to poor quality control but would not expect to see so many Canon motor failures, nor see them draw nearly 2 amps and not even at stall.
Had the same problem with my mth dcc ready engine.Burnt out 2 d123 decoders & hot motor.Recived new motor after calling mth repair service.The motor was over heating & amp'd out the decoders.New motor problem solved.
jalajoie I know of another modelist that his loco came so hot, it distorted the shell. Maybe MTH is overwhelmed with returns and this is why I can't get a reply to my emails. This is not all, a friend of mine bought 3 SD70ACe with Proto Sound 3 factory installed. Out of these 3 loco only 1 retain its cab address, The other 2 will lose programming by simply removing the loco from the track and store it for a short while. At the Chicago MSI museum three of these MTH SD70ACe did not made the grade and had to be prematurely retired from the layout . So much for MTH quality.
I wouldn't retire the loco's. Just replace the DCS decoders with Tsunami's
There are a few catches which I covered in a thread back in Jan of 2010.
rrinker Wow, sure they are using actual Canon motors and not some knockoff lookalike? I can see issues like a drivetrain bind due to poor quality control but would not expect to see so many Canon motor failures, nor see them draw nearly 2 amps and not even at stall. --Randy
I don't know about the DCC ready version but the original DCS version definitely had canons. I noted it when I changed my first one over to a tsunami. Thumb is covering the Canon name.
Sure looks like the same motor in my Stewart switchers. Maybe a different model or something, but the size and label looks familiar. Definitely no problems with multiples of the Stewart locos.
The motor is a decent size. Here's what it looks like in the loco:
glad i read this thread , I was going to look for one at the train show here in jersey today. specifacly an sd70m-2.
I have 11 of the SD7OACEs and have had NO problems with any of these locomotives. I have several friends who also have these locomotives and have had no problems using DCS and DCC. You would think by reading this thread that there is a high failure rate which I know is not the case.
Santa Fe - All the way! Missouri Pacific - Route of the Eagles!
I wish I had your luck Santa Fee Rick, between a friend an me we own 5 MTH SD70ACe and 4 of them are worthless.
My friend purchased 3 units factory equiped with Proto Sound 3. Out of these 3 locos 2 will lose their programming as soon as they are removed from the rails.
My own 2 DCC ready locos overheat decoders to the point they burn out.
So out of 5 locos 4 are bad this is a 80% failure rate.
If only MTH would follow with replies do my Emails.
Sorry to hear about you problems.My advice to you is to keep bugging MTH to honor the warranty and to fix those engines.I have been a MTH customer since 1996 and have only had to return two engines (O scale)for warranty work out of several dozen.It took a couple months but they were fixed.
Rick
If I counted correctly, there were about 15 "good" engines and 10 "bad". Not a very good success rate.
But I'm wondering if these engines came from different batches, or if the problems are road name specific. Is there any way to compile a list?