MTH Premiere (ps2/ps3 upgraded by previous owner) wont chuff, poor speed control

You have the PS/3 upgrade, though the wiring looks pretty sloppy.  The symptoms certainly suggest lack of tach function.  Start by taking readings of ALL the wires to the PCB to the frame.  Only the black wires on the 7-pin connector should have continuity to the frame.  If anything else shows up, fix it before you proceed.  Next, make sure all the tach wires make it all the way back to the board through the tether.  Check that the spacing from the flywheel is 1mm +/- .1mm.  If all of that checks out, replace the tach reader.

Looking closely at the image below, it appears the black stripes are worn through to the white substrate along a narrow band where something has been rubbing against the flywheel, maybe the sensor.

@gunrunnerjohn Do you think the issue could be caused by the tack sensor trying to read along this path on the flywheel where the stripes are essentially worn through?

If the shell is pressing the tach reader against the tape, that could certainly cause an issue!   I suspect the sloppy wiring is likely a primary cause of the issues here.

looks like that black wire rubbed against the flywheel and the tach. (in between)

Thanks for the thoughts everyone! 

This morning I ran through all the pins on the PCB in the tender as you suggested John.  As you noted, only the two black wires on the 7pin connector showed continuity to frame.

I traced all connections through the tether and to the pcb in the tender.  Everything shows continuity, however one thing that stood out to me was that dark blue (tach wire #3) on the engine side is leading to light blue on the tender pcb.  Is this correct.

Light blue on the engine is leading to purple on the tender pcb.  Is this correct?

I dont see a dark blue wire coming out the tether on the tender side.

Regarding the sticker on the flywheel, I'll get some sticker paper, and reprint the sticker, however I don't suspect this is the issue because it was even cleaner before I started tinkering.  Part of the damage to the sticker is my fault.  Ive open and closed it to test so many times, and one of those times I assembled it in such a way that scratched the sticker when the engine ran.  It had the same issue before the marks on the sticker.

I've been using a small ziptie to gap the tach/flywheel.  Thickness of these small zipties I have are 1.04mm, and work perfectly to get the right gap.

The black wire that Joe called out was entirely exposed on the other side not pictured.  I cleaned that up and protected the exposed portion of the wire.

I see something that could be stuck between the sensor and the flywheel tape….maybe???….looks like something white??….maybe a piece of foam tape used to space out the tach sensor that wasn’t removed??…… maybe just me, but take a look,….I’ve circled on your pic what I’m seeing,…

Pat

Sharp eyes there Pat!

Thanks guys but alas no, that's not related.  The area between the sensor and tape is clean.

I'm thinking with the shell on the tach reader is being pressed down onto the flywheel.  I wonder if this would run properly with the shell off?

Also, it's hard to say from this angle, but it looks like some of the contacts are being pushed up in the connector shell, the light pink wire on the bottom seems seated, but the four in the middle seem to be coming out of the connector shell.

I’m seeing that too John,…I know it’s not the OP’s doing but man this thing is a hack job going to a place to fry,……it just looks so dang sloppy,……sorry Loochy88, …I know this ain’t your doing,….but me,…I’d uproot everything and start over,….but that’s just me,…😉

Pat

These MTH J1's were originally designed before PS2 came out, and it's a pretty tight fit.  If you can't get your PS3 to work, the tach-less ERR Cruise Commander might be a better solution for this loco.

Well I worked on it all dang day and couldn't figure it out quite yet.

I did run it with the shell off but it behaved the same as with it on.

I'll have a look at those pins in the tender.

I may try to track down a replacement tach board just to try it.

If that doesn't work I'll probably just swap it to a tmcc system of some sort.  I have several lcru/rail sounds boards I could use, but I feel like this engine deserves something nicer.

I'm not terribly disappointed since I got the model for well under 200, knowing there were issues with the electronics that still seemed like a good deal for the model itself.

@Ted S posted:

These MTH J1's were originally designed before PS2 came out, and it's a pretty tight fit.  If you can't get your PS3 to work, the tach-less ERR Cruise Commander might be a better solution for this loco.

Ted,…it’s great to see you replying again!…been a minute that’s for sure!….I’ve built herds of PS1 & PS2 MTH Hudsons,…there’s no significant tooling changes except for the changes made for wireless ( or wireful) drawbar, ……and that’s just a clearance hole in the bottom of the frame in the back,….as far as boiler shells and other adornments,…no changes,…

Pat

@Loochy88 posted:

Well I worked on it all dang day and couldn't figure it out quite yet.

I did run it with the shell off but it behaved the same as with it on.

I'll have a look at those pins in the tender.

I may try to track down a replacement tach board just to try it.

If that doesn't work I'll probably just swap it to a tmcc system of some sort.  I have several lcru/rail sounds boards I could use, but I feel like this engine deserves something nicer.

I'm not terribly disappointed since I got the model for well under 200, knowing there were issues with the electronics that still seemed like a good deal for the model itself.

You certainly got a descent deal,..so tinkering with it won’t be such a drain on the wallet,….😉

Pat

I'm pretty sure this can be made to run with the existing boards, that's the cheapest option.

@gunrunnerjohn posted:

I'm pretty sure this can be made to run with the existing boards, that's the cheapest option.

Hopefully!  Not giving up quite yet.  MTH stuff always gives me more trouble for some reason.  I always have more luck with Lionel repairs.  Probably just a coincidence...

Do you have enough "hands" and dexterity to position the two sharp-tipped probes of a meter against two exposed metal crimp contacts of a harness connector...while slowly rotating the flywheel?  The 3-wires to the tach assembly form a fairly simple circuit.  There should be a fixed voltage between two of the wires...and a voltage that alternates a few Volts depending on a white or black stripe under the sensor.  There have been previous OGR threads on this.

IF you want to get down into the nuts-and-volts of the matter I think you can isolate where the problem lies.

@stan2004 posted:

Do you have enough "hands" and dexterity to position the two sharp-tipped probes of a meter against two exposed metal crimp contacts of a harness connector...while slowly rotating the flywheel?  The 3-wires to the tach assembly form a fairly simple circuit.  There should be a fixed voltage between two of the wires...and a voltage that alternates a few Volts depending on a white or black stripe under the sensor.  There have been previous OGR threads on this.

IF you want to get down into the nuts-and-volts of the matter I think you can isolate where the problem lies.

Thank you for this info!!!  I will get searching for the other posts.

Ill try to find more details on conducting this test and I'll try to see if I can figure out if it's still good.

I know that with the tach, the outer two wires can be wired up interchangeably, so I assume I'd test it with the center wire and one of the outer?  Not sure about that... I'll try to find more info and get to the bottom of weather the tach is dead.

As far as a replacement tach goes ... Maybe I'm missing it, but it doesn't look like PS3 tachs are readily available anywhere.  Based on a little searching....  The component looks like it might be a QRE1113 optical line sensor. Seems like it's be possible to solder a new one to the board.

https://www.amazon.com/Quickbu...470954011&sr=8-9

I just tried an an OGR search using the must-include-terms "tach blue gray orange" and these will narrow it to the PS tach wiring.  There are several posts by GGG who always has something useful to say...I see some from myself that might apply...such as this one with specific voltages to look for albeit a PS2...but I believe should be relevant to PS3.

Wow.  So if QRE1113 is indeed the replacement part #, it's another one of those shipping costing way more than the part!  But I guess that's life.  I just bought a gasket/seal to repair a leaking toilet; the part was $1 -  shipping was $6.

Maybe obvious, or maybe helpful: When checking small connectors and I need free hands, I often insert a short length of small gauge solid wire into the connector housing, ensuring snug contact with the pin under test.  Then attach an alligator clip lead between the each piece of solid wire and each meter test probe.  This method will add a little more resistance, but this can be accounted for when relevant.  Just checking continuity, the additional resistance wouldn't matter.

Actually Stan, I believe the Omron EE-SY124 is the sensor used on the MTH tach reader.  The QRE1113 is the sensor I use on the Chuff-Generator.  I was actually going to use the Omron part, but it was obsolete, so I changed horses.

The QRE1113 has similar specifications, but a different pinout.  If MTH ever stops making tach readers, I figured I could just lay out that little board for the QRE1113 and it would probably work fine.

@SteveH posted:

Maybe obvious, or maybe helpful: When checking small connectors and I need free hands, I often insert a short length of small gauge solid wire into the connector housing, making contact with the pin under test.  Then attach an alligator clip lead between the each piece of solid wire and each meter test probe.  This method will add a little more resistance, but this can be accounted for when relevant.  Just checking continuity, the additional resistance wouldn't matter.

Being super lazy, and also having been bit by wires coming loose and touching places they shouldn't touch, I frequently just tack the wire onto the connection with a dab of solder.

@Loochy88 posted:

I know that with the tach, the outer two wires can be wired up interchangeably, so I assume I'd test it with the center wire and one of the outer?  Not sure about that... I'll try to find more info and get to the bottom of weather the tach is dead.

Not sure where you get your information, but that is certainly NOT true!

Omron EE-SY124 Reflective Sensor Datasheet

@Loochy88 posted:

As far as a replacement tach goes ... Maybe I'm missing it, but it doesn't look like PS3 tachs are readily available anywhere.  Based on a little searching....  The component looks like it might be a QRE1113 optical line sensor. Seems like it's be possible to solder a new one to the board.

As I mentioned to Stan, that is not the QRE1113, but rather the Omron EE-SY124, which is an obsolete part that you can no longer get, at least I can't.  The QRE1113 could be made to work with a new PCB I believe.  Also, that's a PS/2 tach sensor, the PS/3 tach reader is used only for the diesel upgrade or the factory installations.  The steam upgrade kit mimics a PS/2 board and uses the same wiring as the previous PS/2 upgrade kit.

Are we having fun yet?!

I must have gone to the wrong college, but one thing they NEVER taught me in engineering school was the concept of obsolete parts and what to do about it!

So akin to the MacGyver concept of testing a 9V battery by placing it on your tongue, I'm pretty sure no one on OGR has tried this.  If you're messing with the PS tach, take your TV remote control and aim it at the sensor (obviously the sensor harness loose from the motor).  Press the Channel or Volume up/down button or any button that causes a repetitive action when button is held.  This generates an IR burst of energy several times a second.  Depending on the MTH engine, it can take several dozen IR pulses (reflections from a spinning flywheel) to generate a chuff but this will generate an occasional chuff sound or puff of smoke!  Again, this is in the spirit of the OGR being a discussion forum!

I'm pretty sure you're right Stan, I never even thought about it!

And, as wacky at it sounded, it works like a champ!   You never do cease to amaze Stan, that thought never occurred to me!  However, you can no longer say nobody on OGR has ever tried this, and I have proof.

@gunrunnerjohn posted:

Actually Stan, I believe the Omron EE-SY124 is the sensor used on the MTH tach reader.  The QRE1113 is the sensor I use on the Chuff-Generator.  I was actually going to use the Omron part, but it was obsolete, so I changed horses.

The QRE1113 has similar specifications, but a different pinout.  If MTH ever stops making tach readers, I figured I could just lay out that little board for the QRE1113 and it would probably work fine.

If PS2 tach sensors might be NLA, I guess I’m pretty well prepared for the apocalypse,….😉

Pat

Well now we may be getting somewhere.  I just ran the voltage test on the tach using the directions Stan linked.

I'm getting 1.2v on gray/blue for the led.  Ok, that makes sense.

On to orange and gray for the sensor voltage.  No fluctuations!  Stays at 5v regardless of white or black.

I even put a remote control up to it and read the volts.  Same 5v, remote signal or not.

Strong indication that it's the sensor!  Now I just need to figure out where the heck to find one of these.... Or a suitable replacement...???

Btw, fun fact... I'm sure some of you know, but did ya know you can "see" the ir led using your camera phone (see attached)

YES have used that trick for many many many years a great way for a quick test to see is sensor is functioning !

Alan

I use my camera to check the Lionel IR link between locomotives and tenders all the time.  Also useful for checking the LCS IR transmitter on newer Legacy locomotives.

If you can get a tach sensor from MTH that should solve the issue. Usually (not 100% fail safe) a short in the tach sensor wiring just kills the sensor without damage to the board. Go back and trace all the tach sensor wiring and check for any pinched wires or damage. To be honest trace all the wiring to check for damage. You're locomotive had quite a hack job done on the wiring. No wiring was shortened or routed with any thought. You want the wiring to be more akin to the below images.

@Loochy88 posted:

...

Strong indication that it's the sensor!  Now I just need to figure out where the heck to find one of these.... Or a suitable replacement...???

Per GRJ's earlier post you apparently have the PS2 tach board with an obsolete sensor IC chip.  Seems options are:

1) find a PS2 tach board assembly,

2) replace just the obsolete chip - there's a listing on eBay right now for used chips but must buy 8 for ~$30,

3) replace just the obsolete chip with an equivalent part...possibly requiring delicate wiring if the chip pinout is different (e.g., QRE1113 vs. EE-SY124).

Curious which path you're taking?

Given the simplicity of the PS/2 tach sensor board, it probably makes sense to lay one out for the QRE1113.  Of course, then MTH will start selling them again for peanuts and I'd have wasted my time.

And this is where the announcer says, "Let the games begin!"

Considering this is likely a one-off from the OP's perspective, here's one approach...

From the datasheet, the 4 holes to mount the sensor chip are essentially on the same "grid."  That is, 4mm x 1.8mm vs. 4mm x 1.75mm.  It appears that the parts are NOT mounted flush to the board but are extended off the board by some critical distance.  Once we accept that this is a "hack job" I'd mount the incorrect component at the right height off the board and then cut/re-route traces on the circuit board.  I suggest it's much easier to modify the connections on a circuit board this simple rather than re-routing wires in mid-air to the sensor chip.  I don't know if I'm making any sense.

I realize that 99% of the OGR readership would send the engine in, or scrounge a genuine working PS2 tach board at whatever the going price (plus shipping!)

Last night I bought 5 QRE1113 chips from digikey to mess around with.  I've got a bunch of perf board and a 3d printer.  Between those two things I should be able to come up with a wiring/mounting solution.  We shall see ..

Draw a schematic of the wiring and maybe I can make a PCB that will use them.

@Loochy88 posted:

Last night I bought 5 QRE1113 chips from digikey to mess around with.  I've got a bunch of perf board and a 3d printer.  Between those two things I should be able to come up with a wiring/mounting solution.  We shall see ..

Right.  Please share any DIY findings/insights! 

For the cheapskates (like me!), I found this on Aliexpress.com.  If you are a new customer you can get 10 pieces of the QRE1113 for a net price of <10 cents each after $2 new user coupon.  Yes, you'll have to cool your heels for a month or so as the proverbial slow-boat-from-China meanders across the Pacific but it's hard to resist the price!  Maybe I'm just lucky, but I've had no problems with aliexpress.com to date; OTOH I have had issues with eBay-Asia for inexpensive components like this.  In other words, one of those Your-Mileage-May-Vary.

"We" (the OGR gang) may want to take GRJ up on his offer to design a DIY board for the QRE1113.  I don't know what the MSRP is for an official MTH tach board...but for the DIY'er who knows which end of a soldering iron to hold, I'd think you could make PS2/PS3 tach boards for less than 50 cents each!

Probably should do one of the prototypes and make sure the schematic is right and the QRE1113 works in this application.  A casual look at the spec sheets seemed to suggest it should, but I like to see stuff like this actually working.   Making the board is no big deal, not exactly a lot of components on it.

BTW Stan, I buy my QRE1113 sensors on AliExpress, best prices I've found.  I look for larger lots, I like to buy a couple hundred at a shot.

Yup.  I just looked at the OshPark site and it says the minimum board size is 1/4 sq. inch for their $5/sq. inch pricing which gets you 3 boards.  I measured a couple of different MTH PS tach boards and they were all less than 1/4 sq. inch.

So if I have this right, one could buy qty 3 OshPark PCB's for $5/sq. inch x 0.25" = $1.25 or ~40 cents per board.

Then add a ~10 cent QRE1113 and that's 50 cents per board for the patient DIY'er!