Lionel Berkshire 1946 Smoke Bulb Model

Nice engine. I will let someone else address the speed question. There are post on this site that address using liquid smoke with the smoke lamp.  I think some used fiber glass as a wick. Others just put the liquid in the cup in the lamp.  Be sure that the worm gears (2) have grease.  You get to them from the bottom.  Remove the current collector as it covers the gear box.  Also notice you can check the brush length by just unscrewing the brush tubes. No reason to take the brush plate off. 

That is a nice 726. Can't hurt to service it and get grease and lube in all the right places. However, it is worm driven, so it will be in between your 773 and your more common pinion driven steamers. The red brush plate is a known variation and you can read up about that here: https://www.justtrains.com/Reb...26-1946/726-46-1.asp

I used to have one of those and I always thought it ran slow.  However, I don't collect Lionel and did not have anything to compare it to.  I eventually sold it, when selling off the little bit of Lionel that I had.

NWL

1946 Berkshire and Tubines run at slower speeds because of the double worm drive gears. They are noisier as well. I have one if each. The 1946 models run at a more scale speed. They were not as popular with kids as the later engines, which ran like hot rods. 

The double-worm steamers can run just as fast(or pretty close) as the post-1946 single worm versions, but they must be cleaned out really well and have a full synthetic lube job(including the motor shaft & bushings). I never come across these with much wear on the brushes.

For smoke, I put a 671-181 gasket under the bulb and soak that down with the fluid de jour(MTH & Crown work really well) instead of trying to keep fluid in the bulb depression.

One of my bulb smokers had a 1156 12 volt automotive bulb in it when I got it over 40 years ago and I did the gasket trick instead of changing it out and it still works great to this day. I have no idea why the bulb has not burned out yet either from over voltage or thermal shock or just plain heat inside that closed compartment, but I'm reluctant to disturb it at all at this point.

The light beam from the stack doesn't bother me too much, but I am going to try some high-heat barbecue paint on the top of the bulb when I get around to it to see if that makes it less obvious.

The original 726 Berkshire is a beautiful engine.  I've been lucky enough to corral two of them over the years and yes they do run a little bit slower than the later 726 and 736 models.  They are quite easy to maintenance because of their "BLD A LOCO" assembly.  One thing to be careful of is that when removing the  collector plate to get at that double worm drive there are very small white insulators between the screws and the engine's frame.  These can get very brittle with age and can crack and/or fragment very easily when removing the plate.  The engine will not operate without them.  This happened to me years ago.  You can purchase replacements from Jeff Kane, "The Train Tender" if it happens to you.  Good luck with your 726.  It really is a neat post-war engine.  Loooks great circling the layout.

One other thing.  In lieu of the old smoke pellets which were meant for the 726's smoke bulb I have been using for years the later regular smoke pellets without a problem.  The smoke bulbs still work and no residue has built up on the bulbs.  There may be some who say this heresy and perhaps it is but it has worked for me. 

Thank you for all the comments! I really love this engine! I also just ordered a 1946 smoke bulb Turbine that is "not working" so I can't wait to see this one. Cosmetically it appears to be in great shape.

I will add this 1946 Berkshire to my personal list of very special engines which includes the 225E and 226E. From what I hear I think the 1946 Turbine will make that list as well. The build quality of these is really nice.

The 1946 Berkshire came to me supposedly all greased up with synthetic etc, but I know how that goes so I will have a close look at it to make sure. 

ADCX Rob posted:

The double-worm steamers can run just as fast(or pretty close) as the post-1946 single worm versions...

Check out this 1946 Turbine at speed:

I have had luck using a piece of wire insulation in place of cracked insulators.  Not original but very effective.

There are plastic reproduction insulators at most parts dealers.  When using original porcelain insulators, be reasonable about how much torque is put on the screw.  Also a small fiber washer under the head of the screw helps reduce breakage. 

Although I haven't run it in years the 1946 version of the 726 Berkshire is a well made engine. It will run at scale speed and it is noisy. My version came with turned railing stanchions and a scale tender. The smoke unit does contain a smoke bulb but with some packing and a few drops of smoke fluid in the smoke chamber it smokes fairly well. If you have some of the old #196 smoke pellets do not use them. They are corrosive, flammable and that is why they were only used one year. The later SP smoke pellets don't work well in this engine either.