Chuffing smoke stopped after derailment of PRR LC+ Mikado - fried board?

Sometimes just turning off power to the engine several minutes and then repowering resets everything. This has worked for me with TMCC but not sure with LC+.

good luck

No expert but, if trying to reset everything doesn't work, if smoke is being produced but not coming out of the stack it may be that the smoke fan motor is not spinning. Try to see if you can hear the fan spinning while the engine is on the track and the smoke on. I'm not familiar with your engine, but you may be able to nudge it along by blowing into the stack and see if that helps, otherwise you'll probably have to disconnect the shell and then you should be able to get a good look at the smoke unit and determine if the fan is spinning. It could be just gummed up from excess smoke fluid or the fan motor may be shot. Once the shell is off, try spinning it by hand (toothpick) to see if it spins freely or is stuck. You may just need to free it up. If it was simply stuck, put the shell back on and try it. If it works, run some Eliminator smoke fluid through it to clean it out. If it wasn't just stuck, then take the shell back off and you should be able to disconnect the fan motor and hook up a 5v source to it and see if it will jump start the fan motor (you can try a AA battery, but it may not be enough to get it going or a 9v battery which is too much so only do it for a second or two to see if it moves). If the fan motor spins with battery power applied but doesn't run after you put everything back together, then the fan motor is usually good and the problem is generally somewhere else in the electronics on the board.

It could be that the fan motor that puffs the smoke out has died. That is a common failure on smoke units.

Thanks for all the suggestions. Always appreciate the excellent advice from this forum.

Had a really bad day yesterday besides the smoke unit - my laptop was stolen (argh!), so that has delayed full attention to this issue. Had some time running it with other grandkids today and this is what I can add:

Although I have reset the electronics on TMCC units, not sure how to do this on a LC+ unit. Still no chuffing smoke even after resting overnight.  But after several minutes of operation today at moderate speed, all of a sudden it puffed lots of smoke!  I was thrilled so then slowed it down to see the effect of chuffing intervals...and it stopped again. Nothing since. Still producing smoke, but no chuffing.  Loose wire internally?  

Have not had a chance to check for sound or feel of fan motor.  I have other modern smoke units on diesels that have smoke either all on or all off, but this is the first loco with chuffing smoke, so I do not know how it intermittently kicks out smoke at slow speeds.  Also not familiar with pulling the shell on this unit, so will have to see how to do that.  

Will also add that this unit has had minimal running time from previous owner, so although it is several years old, it's still "new" and appears to be in mint condition.  

Will try more tomorrow.

Thanks again,

Micnael

If you feel comfortable, I would open up the engine and look at it. See if you can test the fan motor.

I have removed the shells from several vintage Lionel locos, but never on a modern unit.  Will give it a try, as I see this is critical to troubleshoot the issue, but not sure where to begin.  

Thanks,

Michael

Michael Pags posted:

I have removed the shells from several vintage Lionel locos, but never on a modern unit.  Will give it a try, as I see this is critical to troubleshoot the issue, but not sure where to begin.  

Thanks,

Michael

If you have removed older shells before, then this one will be just as easy. If anything there will be a plug to undo. Hope you can resolve the issue.

Typically, 6-8 screws on the underside which hold the shell on. You may have to twist the trucks to get at the screws. Once the shell is loose and ready to come off, don't just yank it off. Look for any wires running from the shell to the frame and disconnect them at their plug. There should be at least one for the front lights (head, marker, etc.). The connectors generally can only go in one way, but look and memorize (or jot down) their orientation before separating them. You may also want to take a couple of pictures to show you how everything goes back.

Once the shell is off you should be able to get a good look at the smoke unit and fan and determine if the fan blades are stuck or not or if the unit is gunked up. If the fan spins freely put the engine back on the tack and see what happens when the smoke is turned on - does the fan still spin ? If it's stuck, try blowing on it or freeing it up with a toothpick or exacto blade  and try it on the track again. If it doesn't work, try hooking up a 5v battery/source to the fan motor to see if it spins up and don't let it run too long - a few seconds should be enough to let you know if it's working. Best bet is to disconnect the fan motor first to make sure the voltage doesn't fry anything in the board, but it's your call. If you have to use a 9v battery, I would definitely recommend disconnecting first.

I know LC units use an optical switch/chopper that feeds off the smoke unit piston lever to synchronize the chuffing. Other units, Legacy I believe, use a cherry switch. I don't know which system the LC+ units use. I know the optical units can be tested by moving the lever up and down to block the sensor. If the engine makes chuffing sounds when you do that, then something is probably misaligned and needs to realigned. If the engine does not make chuffing sounds by manually moving the lever, then the problem is with the electronics and you'd be looking for broken or loose connections or wires. That's about as far as I can take you.  

Richie,

I was about to give this a try, then decided first to do a search on the forum to see if there were any posts on removing a shell from a LC+ unit...and I saw your reply!  Wonderful!  I'll give this a whirl. 

Thanks,

Michael

OK, here's the latest info:

I removed the shell. Was easier than I thought; only 6 screws and shell came off freely without any wires connecting it.  Found fan motor and it turns freely.  Applied 1.5 v and operates just fine.  Back on track and no function of fan motor when in motion. Plenty of smoke production, so no problem there.

Then addressed another problem: unit goes dead intermittently.  Same in remote or conventional operation.  After more fiddling, realized will activate when dead if I lightly touch screwdriver blade to any of the middle 8 wheels and outer rail of track.  FYI, I use Lionel tubular track.  Cleaned wheels with DeoxIT D5 and rubbed rails with 99.9% isopropyl alcohol. No better.  It appears the wheels need better contact with rails.  None of my other motorized units have this problem, including vintage locos, TMCC units, and another LC+ unit.  Fan motor not operable at all even when make better contact with wheels.

The puzzle is that the unit worked perfectly for the first 10-15 minutes of operation, even after a few derailments of cars in consist. It was only after a derailment of the loco over an 022 switch that the fan motor stopped, then later the intermittent dead operation started.  One more part of the puzzle - after 10 minutes of no fan motor, suddenly it kicked in. Slowed down the unit and fan stopped.    

Certainly appreciate the consideration. Any other suggestions?

Thanks,

Michael

Partial success: I figured out why the unit was stopping intermittently. There is a small metal strip that is supposed to contact the axle on the rear truck, and it was not.  That is why grounding the wheels as I did with a screwdriver completed the circuit.  I know I cleaned the contact for the strip thinking it was related to the smoke chuff, and must have pulled it out of position.  OK, that's solved and the unit runs smoothly.

Ran the unit with the shell off and saw the fan turn with the chuffs for a short distance. Then it appeared to nudge in motion, but not make complete revolutions, then just stopped. Took it off the track and applied 1.5 v and it turns without hesitation, so I do not think it is clogged.  I looked for a sensor, but I do not know where to look or what I am looking for. Could not find anything that appeared mechanical.  If I knew what or where the sensor is, that might help.

BTW, no problem with the chuffing sound, just the smoke fan not working. 

Well, I'm getting there. Any suggestions for the sensor?

Thanks,

Michael

Try applying some a drop of oil to the motor.

The LC+ steamers do not have a chuff switch, the fan operation is electronically controlled by the electronics with timing off the motor tach.  There's no chuff switch to fix, if the fan isn't running, it's either the fan motor, wiring, or the driver part on the electronic board.

Thanks for further info. The last post from GRJ makes sense, b/c the unit was running perfectly until the loco derailed on an 022 switch.  I do have an external circuit breaker and a TVS unit on the power to the track and this has protected other units from derailments, including this one when some trailing cars derailed, but after the loco derailed, the chuffing smoke stopped.  That's why I wondered if the problem was with the electronics.  Strange that the fan has kicked in some times while running on the track.

I'll keep trying, but may have to bring it in for servicing.

Thanks,

Michael

Here's the latest: I am beginning to think the problem is more mechanical than electrical.  I put the unit back on the track this evening, and nudged the fan motor with a toothpick to encourage revolutions for the chuffs.  Low and behold, the fan revolved, but only for a few chuffs.  Then it gave a slight movement in the direction of turning, but only a nudge.  Continued gentle prodding with the toothpick had the same results - few successful puffs of smoke (3-5), then stopped turning. This is interesting b/c the motor turns continuously when I apply external power with a 1.5v battery.  Not sluggish at all.

So here are a few questions before I take any more steps: 

The posts above suggest a drop of oil or Eliminator smoke fluid. Is one recommended over the other?

Should either go directly into the opening above the fan motor or should I open up the smoke chamber?  

To open the smoke chamber, just remove the 3 philips screws on the top? See attached photo.

Is there a seal on the top piece? 

BTW, the smoke chamber was quite hot after the toothpick scenario. Is this normal for these units?

As always, thanks for any advice.  Getting there...

Michael

You will have to remove the top board to access the fan motor.  At this point, I'd replace the fan motor, it's probably drawing excessive current if I had to guess.  They're a standard Lionel or MTH smoke fan motor, $6-7 gets you a new one.  Oiling, at least in my experience, has a hit or miss record, I just replace the motor if there's any doubt.

• Unplug the smoke unit connectors.
• Remove the top board.
• Grasp the fan impeller with needle-nose pliers, pull straight up and off.
• Remove the two tiny Phillips screws.
• Mount the new fan motor.
• Solder the wires from the old onto the new, noting the polarity of the leads.
• Press the impeller on the shaft, make sure it doesn't bind on the bottom or hit the PCB when it's back on.
• Put the top PCB back on.

It normally takes me ten minutes or so to swap out a motor.

Thanks for the advice and suggestion.  I wondered why the unit works just fine when applying 1.5 v externally, but not on track voltage.  Maybe I just poured too much smoke fluid when first received (applied only 4 drops, but did this twice when smoke production seemed to fade).

Just ordered the fan motor and a few other related items just in case.  Viewed a video on YouTube showing how to replace a similar fan motor, which included removing the entire smoke unit. Is it necessary to remove the entire smoke unit or can the motor be replaced with the smoke unit still on the loco?

Thanks,

Michael

It really depends on whether you can get to the smoke unit on the locomotive.  I suspect you can leave the smoke unit on the locomotive and just drop the motor off, then solder the leads on the new motor before putting the motor back on.

The unit seems fairly accessible, so I'll start with it intact. If I need more access, I'll remove the unit. Just do not want to disrupt the system any more than I must. 

Thanks again,

Michael

OK, I think I fixed it, but need a bit more advice.  I ordered a new fan motor and installed it.  It appears to work just fine!! 

Have not reassembled entire unit, b/c decided to replace the batting. It was rather charred looking.  With the new fan motor, I also ordered new batting for this specific smoke unit and it comes in 8"length.  I have never replaced this type of batting, so I am asking for any advice. Do I use the entire 8" or less? Wrap around the element and reassemble?  Don't want to screw this up.

Thanks,

Michael

You take the batting and pull it apart a bit and then stuff whatever you can fit into the bowl.  Remember, the LC+ smoke unit bowl is smaller, so chances are all of it might not fit.  You want the resistor nestled in the wick, but NOT totally covered, the top should be exposed.  Also, you must allow for airflow from the fan chamber across the resistor and out the stack.  Don't wrap it around the resistor, you'll block the airflow.

Exactly what I needed to know. I'll give a shot, reassemble the entire unit and report afterwards. Many thanks for the great advice.

Michael

We look forward to the video.

OK, you asked for it!  See video.  Near perfect success. Definitely have smoke with the chuffs (took video of loco at low speed).  Does not seem to be as prolific as before, but may not be all that bad.  The room was filled with smoke after just a few minutes when I first received the unit and before the fan motor died.  Also, shortly after I took the video, the smoke puffs stopped. Oh no! Removed shell, fan motor revolved just fine, even with external 1.5v applied, ran on track with shell off and seemed fine, so put shell back on, and presto, smoke again. This time seemed to prevail. Have not run the unit more than just a minute or two. 

Manual indicates to apply 4 drops of smoke fluid.  That's what I did, but had very little smoke, so I added 4 drops more. Should I add any more with brand new batting or just be satisfied with the current smoke output?

Thanks again for incredible advice from this forum.  This LC+ unit is a great little chuffer, and I know my grandkids will love to operate it

Michael

We have smoke, you are done!   Looks good, glad it was a cheap fix.

Yes, it works, and I am very grateful for the advice. I learned a lot along this journey. 

Enjoy the weekend.

Michael