“Troubleshooting MTH Jerky Engines”. In the last five months, I’ve had six MTH engines develop a jerky symptom that prevents the engine from being operated. With the engine shell removed, the rear can motor flywheel can be seen, coming to a complete stop while the front can motor continues to operate without hesitation. The jerky symptom is so pronounced, that any speed, over 3 or 4 mph, is likely to damage the engine components.
All engines, except one, were factory P-2 engines. Engines range from years 2000 to 2008, and have different operating hours from up to 119 hours to a low of 3.5 hours. All engines, except two, were the trailing engine in a lash-up. The layout is 2800 sq ft with two levels of track. Level 1, in addition to TIU 1-4, also has three TIU 5's and four Z4000's with only one light grade of a climb of 5 inches in 24 feet. The level two layout portion also has 3 TIU 5's, four Z4000's and one TIU powered with four 180 Watt Power Supplies with one per channel. (The track loop that has the 180 Watt system, does not have a track connection to other track loops.) There is one grade that has a climb of four inches in 16 feet. Except for TMCC engines, a lash-up on either grade, does not result in a noticeable increase in either amp or volt readings on the Z4000. Each grade is on a separate channel of a TIU. Train lengths average around 22 cars with a mix of Atlas, MTH, K-Line, Weaver and Lionel. Some cars are weighted to match the heavier Atlas cars. Also, I’ve disabled the caboose rollers on each train to reduce the train length signature while moving from one TIU channel to another. Since the problems started to appear, I’ve reduced train lengths in a lash-up, by abut 8 to10 cars On each level, a train will pass over power from three different Z4000's with the center pin insulated for each Z4000. On that long of a loop I can run up to four or five lash-up trains at the same time while maintaining equal space between each train by setting all at the same scale mph. The load on each Z4000 usually is at less than 3 amps and the voltage staying steady at 18 to 19 Volts.
The first engine’s problem was found during an operation session with the rear engine uncoupling from the lead engine and derailing. The lash-up had been in place for at least one year of operation. The rear engine had developed a very jerky performance and with the rear can motor not operating correctly, I diagnosed the problem as a can motor brush failure. The second incident also occurred during an operating session with the rear engine in a lash-up with a P3 engine on the level two layout grade. The rear engine uncoupled and derailed causing the TIU to shut down with a red light. I removed the two engines, substituted a back-up lash-up set, and then restarted the operating session without incident. The next day I put the derailed engine on the layout controlled by a TIU 5 and at first there were no symptoms until the engine warmed up after about 5 minutes and then it displayed a jerky operation. I removed it from the track. I then went to another building and put the engine on a test track with a TIU 1 and different hand held remote and the engine was also very jerky. No matter what I inspected from lubrication, to wiring to wheel cleanliness and engine shell on or off, allowed me to determine the cause of the jerky operation.
The next jerky engine problem surfaced during a series of engine movements to re-position a train in a specific location. The lash-up started normally, however; the lash-up seemed to have a drag and then the rear engine became jerky. I removed both engines from the layout, cleaned wheels and track, and re-installed the lash-up. Within about five feet of operation, the rear engine developed a very strong burning smell and I shut everything down. I didn’t try any troubleshooting as I assumed the engine had damage requiring a P2 repair. The two engine lash-up had been in use for over three years and had 162 miles and 36.3 hours of operation. It never had been on the level two or it’s grade.
While searching for replacement engines, as I looked for substitutes, I found three more
engines that when they had been put in storage, with a fresh battery, were operating correctly and now exhibited the jerky symptom when placed on the track and powered up for forward movement. One had been in a lash-up, however; the others were low hour usage with one having only 3 hours and the other 4.5 hours on it.
A word about engine lash-ups. Prior to actually permanently assigning a lash-up to a set of engines, even if they are identical models and date of manufacture, one engine should be placed about three feet in front of the trailing engine. Then after starting the “lash-up”, one should observe that the engines are really synchronized to each other’s speed, with no more than the slightest tolerance of speed difference allowable to insure each engine is actually matched to one another. Also, one should consider that the freight cars attached to the trailing engine will make even the best synchronized pair, a little different in pulling effort. That difference is surely more if there are significant grades on the section of track that the lash-up travels. I use a ten pound weigh scale that measures in ounces. I try and weight each car so that a 40' car weighs 16 ounces and a 50' car weighs 19 ounces. Atlas 40' cars, right out of the box, often weigh more than 20 ounces. Since not every car is an Atlas 40' car, mixing in 50' cars of Atlas and other manufacturers, requires some of the other cars to require additional weight to match. If one runs a level layout and uses only 10 or 12 cars, without any grades, weighing probably won’t be an issue. Even using two engines in a lash-up, pulling 20 or more cars up a grade, in a 138 inch curve might work. However, when coming down the grade, especially in a curve, requires the cars to have been weighed or the heavier cars on the rear of the train will push the lighter cars off the track and result in derailment headaches. That being realized for larger layouts, I try and keep the actual load on the lash-up engines equal to what the engines are trying to pull. Two GP-9's obviously can’t pull up grades the same as two SD-70ACe’s. I average about 20 cars per train, however, if they’re GP-9's, those cars will have a cumulative weight much less than larger engines and the weight of their cars cumulative weight. After a lash-up has been running for two or three years, pulling the same cars, one should separate the engines and re-examine their performance. I didn’t do that until the issues I’m working with started. Examining the voltage and amperage of each train is a good tool to use for performance checking. That works as long as the track and engine wheels stay clean. Tracks and wheels don’t stay clean so once a year I clean all the track and wheels before the beginning of each operating year which is usually September.
How accurate is a weigh scale? I use a package of 16 “one” ounce fishing weights sealed in its zip lock bag as a test for calibration. The post office weighed my bag of weights at 17 ½ ounces. As temperature and humidity change, so will the scale’s weight shown. However, the 17 ½ ounce bag never changes and placing those on the scale first, insures that you most likely are very close to the real weight you see on the scale when a car is packed on it. So, one may want to examine the failure of these engines as faulty lash-ups and that would be a very good consideration if all the engines had been in a lash-up. Subsequent downloading of sound files fixing the engines wouldn’t seem to be connected to their jerky operation if it was a lash-up to weight related cause? It seems like there’s a software issue that might be a result of a signal issue? I’m not an electrical expert, so I can’t even make a good guess compared to the OGR moderators expertise.
So considering all that I know and out of ideas, with the fear that I had an operating problem within the layout or multiple TIU 5's, I called MTH and talked to Dick Caster. He told me, without any hesitation, to download new sound files into each of the problem engines. After several weeks, I managed to coordinate a repair session with a friend 50 miles from me, as my computer is too old and full to load the MTH System Program. Finding replacement files with the same P2 systems wasn’t that difficult and all engines had a newer sound file installed. The first engine had a little hesitation on it’s move forward and I thought we might be wasting our time. However, the next engine was the one that had the strong burned electrical smell and after the sound file download, it ran perfectly The very last engine was the oldest with a 2000, V-3, P2 sound system. We took the next generation’s available and it downloaded without getting an “Incompatible” message. However, it was slightly hesitant on it’s move forward and had a little speed fluctuation on running around the 40 foot loop. We increased the speed to a scale 80 mph and later a scale 120 mph and after about 7 to 8 minutes it became smoother and smoother. After bringing the engine to a complete stop and restarting it’s forward movement, it had the very slightest, one time hesitation and then would run without any further defects.
After getting back home with all engines running nearly perfect, I installed a new TIU on my test track and then reset the remote to “factory”. All engines ran as they had at the other layout. However, one engine had lost a front traction tire on the "sound download layout", that had been the first one with the new sound file and the slight hesitation that was still with the engine after the sound file downloaded. We had taken that engine, that had been set a side, and re-ran it to smooth out the performance problems. So, before putting that engine on my test track I replaced both front traction tires. It’s an engine that had a very easy shell removal and re-install process without a lot of wires to negotiate upon re-installation of the shell. I put it on the test track and the symptoms of the jerky engine reappeared? I removed the shell and ran the engine and I could see the rear can motor flywheel coming to a complete stop for a moment as the front can motor performed normally.
I called MTH again and couldn’t get Dick Caster, however; the Service Rep. had never heard of that process of downloading a new sound file. However, he surmised that the sound download also affected other items and could possibly be similar to a “hard drive reboot” He also brought up the possibility of static electricity. That is an interesting observation, however; three of the engine failures occurred over a two month span without physically touching any of the lash-ups. The replacement traction tires and the battery recharge, or replacement on the substitute engines, does not rule out static electricity, however; I’ve never felt a slight shock or had any problems with over the 100 other engines that have had maintenance. That’s including the removal of the screw to the powered truck block on the improperly coated P3 engines, that I had significant exposure to the power boards and other electrical components.
So, I’ve come back to the reliable OGR Forum and it’s significant resources of information for some guidance, clarification and suggestions to help me determine the most likely cause of the jerky engines. Since the five engines developed problems, I’ve run at least 3 different lash-up over the same routes and they perform perfectly normal. Can multiple TIU 5's, with one having a operating defect, cause an engine to exhibit what I’m experiencing? I’ve already gone back and re-installed each TIU 5, one at a time, as per the instructions in the DCS O Gauge Companion on page 119, by using two separate remote’s and TIU’s. However, until I can insure that the layout is operating correctly, I haven’t even started an engine on the layout for over a month. I thought that if the downloading of the sound files worked, it could provide some clarification of the problem. That hasn’t been the case. However, I know that dirty tracks, dirty wheels, lack of lubrication, pinched wires, a layout flaw that causes all engines to not perform correctly, amperage problems, voltage problems and a lot of other circumstances, has not let me determine what is happening and what might correct the situation.
Summary of Engines that failed.
20-2105 P2 added in 2006 no lash-up 4:57 hours of op New file 20-2913
20-2359 P2 issued 2003 no lash-up 38:38 hours of op New file 20-2913
20-2660 P2 issued 2008 lash-up 36:36 hours of op New file 20-2913
20-2660 P2 issued 2008 no lash-up 3:59 hours of op New file 20-2913
20-2459 P2 issued 2006 lash-up 28:38 hours of op New file 20-2913
20-2270 P2 issued 2000 lash-up 119:25 hours of op New file 20-2558
20-2778 P2 issued 2007 lash-up 21:21 hours of op Not avail for download (I didn't take it to the
download layout as I had no idea it would fix
an engine that I thought was a can motor issue)
Comparison of an engine that has not failed after 118:20 hours is 20-2255-1
In advance, thanks to all who take the time to read through this information. I regret that the data consumed so much space, however; if you feel any of the information is irrelevant, just skip over it.
Two Attachments Included showing track plans and TIU 5 locations and tracks they control.
"Track Layout Level One", "Track Layout Level Two Above Level One"
Thank You
Moke Mike
