The consequences of not putting smoke fluid in an MTH loco

Tell the guy you can trade him two of your $300 cats for the locomotive, and he can come out ahead on the deal.

I actually used this on a person trying to get to me on a deal.  They don't like it, but it does wake them up.

Thanks for posting this..i always thought that if you ran your smoke unit dry because of the lack of fluid for cooling or whatever the resistors could burn out and become "open". Does this open condition precipitate other failures down the line?

I don't understand how they managed to do it but the elements actually didn't fail, the resistance was still 8 ohms which was odd but the fan motor was a dead short. My guess is the unit go so hot the motor couldn't handle it and shorted causing all the other issues

I suppose a fet failing closed would turn the heat up way too high

Don't these units come with an on off switch?  Why not simply use it?  If it doesn't why not install one to avoid the issue altogether?

Matt Makens posted:

I don't understand how they managed to do it but the elements actually didn't fail, the resistance was still 8 ohms which was odd but the fan motor was a dead short. My guess is the unit go so hot the motor couldn't handle it and shorted causing all the other issues

That makes sense..a shorted armature draws excessive current and no real over current protection in the circuit. good call

I always put the smoke unit switch in all my engines in the off position.  I never put fluid in them.  I hope that his won't happen with the switch turned off.

NH Joe

Joe, I just can't see a switch that's never used failing. I wouldn't worry about it at all

Matt, That blue wire is PCB ground not smoke.  The fets are the fan fets that blew, not heater element.   So it is possible that the fan motor failed(shorted).  Stopped blowing air which toasted the wick.  Once the overload shorted the smoke fan fets.  One is go and the other stops the fan you had a direct 5V to PCB short.  Once the blue wire overheated and shorted that could have taken the board out.  SO I would not accuse the customer of not adding fluid, but he may not have been aware the smoke fan was gone and the smoke unit was still on.   G

Matt,GGG..i wonder if a properly rated axial fuse in the circuit would help to protect from damage.

http://www.littelfuse.com/prod...uses/pico-fuses.aspx

ouch sorry 'bout that man 

hope you get it fixed 

yellowstones are nice

i plan on getting one myself

Many people who cannot work on things themselves do not understand how things work. Following that, they do not understand how they may be damaging or misusing something, simply because they do not understand what is going on under the hood. They also have a hard time understanding how some things can be more difficult to fix than other things, especially things that they have misused and damaged.

That's one of the difficulties with fixing things for other people.

I cannot see how not adding smoke fluid would cause an electrical failure other than burning out the smoke unit.

If the smoke unit gets really hot and shorts or kills the motor shorted, it can do significant damage elsewhere.  Normally, I'll agree, it just cooks the smoke unit.

Kazar, DCS system can override the on-off switch, which only controls in conventional.

I never use smoke, but I try to keep the wicks wet just in case it gets turned on.

It is wise to get a substantial deposit in advance before starting expensive work. 

RJR posted:

It is wise to get a substantial deposit in advance before starting expensive work. 

If they don't pay, I get a working engine, so I rarely take a deposit. 

Thanks John, my thoughts exactly. I see no reason pay him $500 for a loco that I only think is worth about $700 if I were to sell it as is. I already have 2 Yellowstones so I don't really need a third but hey, Ive got a good size layout, i bet it would look cool double headed with my other MTH Yellowstone. Ive already got this engine fixed. I explained to him before I fixed it it needed new boards and rewiring ans was going to take a significant amount of time, he said go ahead and fix it so I did. If it wasnt worth fixing I would have walked away. Thanks G I didnt pull out any wiring diagrams to check it just pointed me in the direction of the power hog circuit.

That board may be repairable if only the smoke fan fets damaged, and traces not burned out.  Though I imagine the audio amp is also toast. The audio amp does not like disturbances to the 5V power system, nor AC voltage spikes.   G

So...you were going to charge him $464 but instead he's giving you the loco that you say can be sold for $700, which seems to increase your profit exponentially, and this doesn't work for you?  I don't think I follow ...

Well, I'm guessing Matt thinks like I do.  I don't want to accumulate engines that are sent for repair, I want to accumulate the money that was owed for the repair.  

G, I Valentina actually tested the processor board because it smoked out the power board and I don't wanna kill my las ps2 3v power board. I'm not as proficient at fixing the boards and I have no idea where to start with a dead power board. I'm with John, I don't want to accumulate locos that I repair, this is a decent loco but has a rust line down one side of the boiler and no box, I don't like locos without boxes, they don't store well. 

John, so if you get a working engine, will your grocer take it in return for food?

I take my hat off to all the repair guys on the forum.. It's not an easy job..

Complaints.... The head light  lens  is missing?..  I better check my layout , it could have fallen out while testing.

   Where did that scratch come from?    I never noticed it before.

  It's stilll not working     (operator error)   etc.

These boards are just so touchy and expensive and you usually don't get a second chance if you mess up.

RJR posted:

John, so if you get a working engine, will your grocer take it in return for food?

If I have to worry about paying for groceries, I have a whole different issue. You're inventing problems where none exist.

I have yet to have anyone refuse to pay for a repair, and I seriously doubt it's going to suddenly become a major problem. When I start having to worry about those kinds of issues, I'll cease doing any repairs.  I also communicate with the person in advance for any expensive stuff to make sure they understand what it's going to cost, that's just common sense.

I have had a couple of people tell me just to keep it when I give them the repair estimate and tell them what it needs.  I'm guessing they already had a good idea that it would be too expensive, but just wanted a second opinion.  I've also had people put an insane amount of money into something that I'd never consider, but they obviously have an attachment to the particular item.

GRJ - ok, understood.  In essence, you're saying that despite the ability to make more money by reselling the engine, the "less hassle" route is favorable.  I'm often of the same mindset, because the reselling route also means more of my time and effort.  It was curious to me in this case only because of the amount of money.  The "resell" scenario seemed to almost double the entire bill - parts and labor - so that seemed like a huge profit windfall.  

This guy wants me to give him $500 to keep this engine, thats s new one. The same day another guy asked me to buy the repair he sent me this one is a G scale challenger. I didn't realize things were getting that tough. Seems like I'm getting set up

John, if you've never been stiffed on a fee, be thankful.  I know an excellent marine engine technician who, to hear him tell, constantly has people trying to stiff him when they get a bill for $5000 or so.  He does not operate a marina, so he can't hold a boat like you can a train, until he's paid. ANd he and his family need the money, not only for groceries, but to pay for the parts he used.

Look at Matt's situation.  He's stuck with an engine he doesn't want, which he can't sell to another since he doesn't own it. 

Matt, are you saying he's now brought another engine for repair?  First time, shame on him; second time, shame on you.

I guess I'm just more careful how I select my customers.  If I had people constantly trying to stiff me on repairs, I'd simply stop doing them.  If someone refuses to pay me for repairs on something, I'll just hold on to it.  Eventually, I consider it mine and sell or use it.  However, since I've never faced that situation, I'm not that worried about it.

gunrunnerjohn posted:

If the smoke unit gets really hot and shorts or kills the motor shorted, it can do significant damage elsewhere.  Normally, I'll agree, it just cooks the smoke unit.

I don't know that much about these things, but it seems amazing (and a bit odd) to me that there was enough heat generated to go back up that blue wire and burn the insulation off of it.

The current through the blue wire is what cooked it, not the heat from the smoke unit.

I just had a PS3 imperial allegheny that the smoke unit was not sitting right and it was hitting the shell and eventually rubbed through the heating element wires and took out the boards.

I guess there's no fixing PS3 boards like ps2. I've replaced many FETs on 3volt and 5volt boards. Those I did fine. When it came to the audio amps I sent it G. Lol

it suck that people don't want to pay for your work. I haven't had that happen but we recently came across an engine at the hobby shop I fixed a year ago. They never came to pick it up and we called again and the guy had passed away. They told us to keep it and sell it. But it sucks to call a customer and find out they passed away. 

Ralph

I haven't been to MTH since 2013, I'd like to go to one of the PS/3 classes to see if they're handing out some information to at least replace lamp and smoke drivers on the PS/3 boards.

When I said "another guy" I meant some other totally different guy

Why did you think the blue wire was for the heaters?  With the engine hooked to the tender, did you test continuity from the 4 pin connector 0n the PS2 processor  board (smoke) to the smoke unit and fan motor?

Marty, I didn't, there is no blue wire on the smoke unit but the only thing that draws current like that when it fails is usually the smoke unit.

Matt, yes you did, you stated -----"wires melted and the solid blue wire(smoke unit heater) to be missing insulation the entire length of the wire. OOOOH the smoking gun, that is  why this loco died"-----You threw it out.  

Matt, I know there is no blue wire on a smoke unit.  I know what the blue wire is for.  You stated above it was for the smoke unit heater.  I was curious where you came up with that.  

Interesting subject on 2 levels now.   Breezin Up,  The Blue wire is DC Ground,  Purple is DC positive.  So they are equivalent to the Red and Black AC wires on any train.  If you had a derailment and direct short on a conventional engine that did not clear, either the red or the black AC wires would overheat carrying excess current.  Same for Blue or Purple wire depending on where the short occurred.

Funny subject on paying.  I always give estimates and get approval before repairs.  I don't charge until repair is complete.  If work grows, I give new estimate.  I do have customers that send money with repair.  I only had one customer not comeback for repairs, but then called 2 years later and settled up.  This was local.

One death, doing contract repairs for some one else.  The estate paid the bill and the train was shipped to the estate.

A few donations of inexpensive trains when the repair bill was going to be higher than the value of the train.

Many customer that want to be sure I am paid for my time evaluating things even if not repaired.

And a couple of customers very gracious when shipping damage occurs, which is very comforting.

Less then 5 customers I would call difficult.

The bottom line, the train repair business customers are great people.   G

Marty, I misspoke not sure why I wrote it up like that because not that I think about it it wasnt the wiring that led me to the smoke unit, it was the blown fets on the board. Only after did I find the wiring issue. This was a particularly long repair since I needed to order parts form MTH and it took over 5 weeks to get the mux board I didnt have in my arsenal.