Lionel Smoke Unit (6-28544 RS11 TMCC) - resistor wont heat.

You're looking in the wrong place.  It's likely not the smoke unit.  This locomotive has the infamous smoke voltage regulator, a common failure point.  The smoke regulator is actually the part that supplies the power to the smoke resistor.

The smoke resistor should measure around 8 ohms with an ohmmeter.  You should be able to easily trace the wires to the connector of the smoke unit and measure it there.  If that rings out, start looking at the smoke regulator and smoke switch wiring.

Please help with proper wiring for the 691-ACRG-EO1   Attached is a pic of what I have

There is a black and white wire on one side and a black and yellow on the other side

That doesn't look like the smoke regulator.  The Lionel smoke regulator board has five wires on one side, two of them being grounds, so sometimes the second one is trimmed off.  Classically, they're heatshrunk like the one I posted above.

That might be a 5V power regulator used in some engines, look around for one that has red, brown, black with brown strip and one or two black wires.  The 691-ACRG-E01 is the one that is specified in the parts listing for your locomotive.

Right. I found the smoke regulator. Thanks

When you get the new part, I typically just chop the wires near the old one and splice the new one in.  It's much easier than trying to follow the wires to the end.  Make SURE you get the colors right, the black with the brown stripe is hard to find on some of them.  Don't connect that wire to ground, bad things will happen.

Yes. I saw your advice in another post. I will definitely splice the wires. Thank you very much.

Mine has a brown with a thin black stripe and the 2nd black is cut off. 

Yep, common to lose one ground.  Just make sure the colors match, and the brown stripe goes to the new one the same way.  There should be a red (track power), brown (serial data), black w/brown stripe (smoke element), and one or two black (frame ground).  If you confuse the brown and brown stripe, you'll be replacing anything that uses the serial data!

     I have red, black, brown and a brown with a thin black stripe. Not black with brown stripe. 

Same difference, you have a striped one with brown and black.  Like I said above, they have all different combos of the brown/black from almost brown to almost black.

understood. thanks

  I have 1 loco thats had a regulator getting flaky for some time.

What do you recommend using to splice these small wires?

I just cut them, strip them, and then tin the wires on the new regulator and the wires that used to go on the old regulator.  Slip some heatshink on the wire, and solder them.  Put the heatshink over the splice and shrink it with a heat gun.

My splices for stuff like this are just about 1/4" of the wire tinned and lay them side by side and heat.  You're not trying to suspend a bridge here, just have a good solder connection.

Thanks John ! Got a link to the proper heat shrink?

I really don't have any links, I buy my heatshrink in reels.  I just grab something that slips over the wire and will shrink tight, the diameter is dependent on the size of the wires.  I keep stuff from 3/64" to 3" around.

Fair enough. Thanks again!

         I use liquid electrical tape. Google it

I don't have to resort to Google, I've used it for years.  However, Liquid Tape is not nearly as tough as heatshrink.  For wiring stuff like this I prefer heatshrink.  Heatshrink is also much quicker, a quick blast of hot air and the joint is insulated and I can move on, I have to wait for Liquid Tape to dry before I can stuff the wires away.  I find Liquid Tape great for certain jobs like blocking light from lighting installations where I don't want it, etc.

is it ok to connect both black wires?

As long as both black wires are ground, it's fine.  They're common inside the smoke regulator.

so i replaced the regulator, fan runs but resistor doesn't heat. 8ohms measured at resistor

I think I'd have to see it, obviously there's a disconnect somewhere.  If the regulator is good and the smoke unit resistor measures 8 ohms, it should heat.  Time to break out your meter and see if everything is wired right and if power is actually making it to the regulator.  Is the smoke switch on?

would the fan run if the switch was off?

Truthfully, in looking at the smoke unit that is supposed to be in that unit, I don't see how the fan runs unless power is actually getting to the smoke unit.  That appears to be a totally dumb smoke unit that powers the fan from the smoke heater voltage.  That being the case, I can't imagine this being anything but an issue right at the smoke unit.

Sure, smoke isn't turned off on the cab 2

While on regulators, Do you (Gunrunner) know the difference in the codes? 

No Chuck, I've never seen that documented anywhere.  I've asked a number of people, never found out what the codes specify.

There was a bad connection at the switch. Interesting that the fan would run but the resistor would not heat until I fixed the connection. Thanks for all your input.