Which Polar Express Loco???

Well, the LC+ locomotives are the ones with the fan driven smoke.  It might be possible to transplant the PE boiler and tender shell to a Berkshire LC+ model chassis, but there will be some work involved.

I solved the problem with mine by converting a conventional set locomotive to TMCC with fan driven smoke, etc.

GRJ, or anyone that has a LC+ Berkshire, what's the difference in the mounting points and such between models?  could the smoke unit and hardware from an LC+ Berk be transplanted into the polar express?  

Whatever the case on that, the arm of the puffer unit controls the chuff on the polar express so you'd have to either keep the arm in place or come up with a new chuff switch.  

I'd be looking to just swap shells, hard to believe they are that much different.

Swapping shells is easy, but you would lose the polar express sounds doing that.  On the other hand, you would gain the cruise control, electro-coupler, and sound volume adjustment.

I don't see any way you're going to keep the Polar Express sounds, but maybe that's just me.

So, I pulled apart a polar express, and my NW2, which uses the same smoke unit as many other LC+ engines including the Berkshire.  I don't see any reason one couldn't fabricate a new metal bracket to hold the blower unit instead of the puffer and perhaps a piece of foam to make a nice seal around the stack.  The electronics are a bit more annoying as the polar express engine doesn't have any method to vary the fan speed or to match with chuffs in it's design.  One could wire the heat element and fan directly to the same power used for the puffer, but this would spin the fan at full speed whenever the engine is moving, and run at full heat, quickly using up smoke fluid.  I think it's possible to build a small circuit to tap into the chuff sensor to spin the fan in time with it, but that may be beyond what the OP is looking for.

Edit: come to think of it, I think that's exactly what GRJ's super chuffer would do, wouldn't it? Maybe with some hacking to use the LCPE's opto sensor and not disturb the original electronics. 

JGL, someone has already built a circuit to manage the smoke fan.

 Super-Chuffer II

JohnGaltLine posted:

So, I pulled apart a polar express, and my NW2, which uses the same smoke unit as many other LC+ engines including the Berkshire.  I don't see any reason one couldn't fabricate a new metal bracket to hold the blower unit instead of the puffer and perhaps a piece of foam to make a nice seal around the stack.  The electronics are a bit more annoying as the polar express engine doesn't have any method to vary the fan speed or to match with chuffs in it's design.  One could wire the heat element and fan directly to the same power used for the puffer, but this would spin the fan at full speed whenever the engine is moving, and run at full heat, quickly using up smoke fluid.  I think it's possible to build a small circuit to tap into the chuff sensor to spin the fan in time with it, but that may be beyond what the OP is looking for.

Edit: come to think of it, I think that's exactly what GRJ's super chuffer would do, wouldn't it? Maybe with some hacking to use the LCPE's opto sensor and not disturb the original electronics. 

John, Whats the P/N for that smoke unit. I thought about the smaller MTH unit I saw in a thread yesterday, GRJ posted up.

The LC+ smoke unit I use is this one.  I've put them in a couple of small things where I couldn't fit the MTH unit that I normally use.

6803605200     SMOKE UNIT W/ 691SGSUA01 / LIONCHIEF PLUS / 15 MM     $35.00

gunrunnerjohn posted:

JGL, someone has already built a circuit to manage the smoke fan.

 Super-Chuffer II

Yeah, I mentioned that in the edit like 10 minutes after I posted last night.  Thinking more the super chuffer combined with the tach strip reader board of yours would probably be all you need.  I'm not familiar with the specs of the super chuffer so un sure how it would be wired up in this case.  The LCPE provides 5vdc to the smoke unit when the engine is moving in either direction after the 2nd or 3rd speed step, about 3vdc for those first steps, and 0 when in neutral.  

Jayhawk500 posted:

John, Whats the P/N for that smoke unit. I thought about the smaller MTH unit I saw in a thread yesterday, GRJ posted up.

This is listed as:  680-1301-250 however looking closer it's one of those 'must contact lionel' parts.  it was just the fan unit that was easiest for me to get to, but anything around that size should be able to be made to work.

You can buy the part, Lionel just likes to control the quantity of certain parts, so consumers can only order one I believe.

It would be possible, I suspect, to tap into the chuff optical chopper to run the Super-Chuffer.  You might need a transistor buffer, but it could be done.

The smoke unit heater voltage is probably what it is, unless you wanted to simply provide 5V all the time.  The stock LC+ smoke resistor is 16 ohms, but I haven't checked to see what they provide as power.  I know the LC+ also turns off the smoke when you stop.

Both my LCPE and LC+ NW2 provided 5VDC to the resistor (and fan).  on the polar express, if I recall correctly the optical sensor provides a low pulse, and this could be tapped directly into a microprocessor without causing any problems.  at least it worked fine when I was messing around to see if I could make it do 4 chuffs per revolution.  ( that didn't end up working out very well, sounded like crap and the sounds couldn't keep up) if needed you can also tap into the connector for the opto to get a constant 5vdc source to run a uP.  

As for the smoke running or not, I think it depends on the engine.  on the NW2, it runs the fan slowly and turns down the smoke but still smokes at idle.  I'm unsure if the lc+ steamers do that or not. 

side note, after not using the smoke for the last 3 years or so, it looks like I need at least a new motor.  it's squealing like crazy.  

JGL, It's possible a tiny drop of lightweight oil on the smoke motor shaft will help the squealing. I am not familiar with that smoke unit, but there have been a couple of threads/videos of folks having success with that method. Might be worth a try before replacement?

Many of the smoke unit motors seem to be fairly similar. I have replaced a Lionel Legacy smoke motor with an MTH smoke motor and they were pretty much the same motor as far as I could tell. Worked fine and it's still working after 3 years or so.

LC+ Steamers turn the smoke off totally when stopped, I checked when I got my Camelback.  I'm pretty sure the others do as well.  It would have been cool for them to have idle smoke like the diesels, but nooooooo.

The low pulse from the LC chuff opto would work fine for my Super-Chuffer as long as the signal didn't mind the 4.7K pullup and the .1uf cap that is across the chuff input to prevent spikes from hitting it.  Actually, there's a 100 ohm resistor, the .1uf capacitor, and the 4.7k PUP in the circuit to the input port.

Rtr12 thanks.  I was planning on trying the oil drop at some point.  As of now I don't even have a single loop of track set up to run on, so fixing the smoke isn't a top priority for me.  when the time comes I'll look into something suitable that isn't likely to gum up over time. I'm unlikely to have a place to run trains with smoke for a while. 

As for the superchuffer, I don't see why the pull-up et al. would be a problem, but not worth the trouble to test it unless the OP wants me to.