noswad,
The 1946 Lionel 726 Berkshire is a great engine. The early 726 and the later 726s and 736s were different in several ways. The two different style locomotives used different motors, different smoke generators, different E-Units and different boiler and frame castings. The details of the body and gearing construction are not interchangeable.
I have two of the early 726s and run them quite often. They are not quite the pullers that the later 726s are and certainly are not as strong as the 736s with magne-traction.
I have never used any type of smoke fluid in the lamp style smoke generators using strictly the old Lionel SP smoke pellets as well as the repros. I do not know what affect, if any, fluid would have on the smoke bulb although recently someone posted on the forum that they placed some old asbestos insulation on top of the bulb and then applied smoke fluid and the engine smoked great. For whatever its worth the old smoke bulbs did not produce a prodigious amount of smoke. Nevertheless, I think they are kind of neat simply because they are different.
The horizontal E-units in my 726s to date have not caused me any problems. Having said that I will probably now be confronted with some. I have cleaned the E-unit drums a few times as part of routine maintenance and have found these units no more difficult to work on than the regular E-units. If need be, replacement units are readily available through Jeff Kane, The Train tender.
Maintenance of the double worm drive is really quite easy since the bottom plate completely drops out providing easy access to the double worm drive. This kind of follows the pre-war build a loco concept. One thing to note here is that the cover plate assembly uses several white plastic or ceramic insulator bushings between the plate assembly and its screws. These can and will crumble with age. Without them in place the engine will not operate. Again, replacements are available through the Train Tender as well as others.
As I have mentioned in other posts having an early 726 is kind of neat because it offers one a good look at early 1946 Lionel Technology. I think its fun to compare the technological progression in the manufacture of these engines so I have both the early and later versions. The early 726 while not as strong a puller as the later models is still a smooth running engine and can pull a consist of four or five freight or passenger cars.
If you get one I'm sure you will be happy with it. Good luck.
