Lionel motors used in steam engines post MPC

The smaller Mabuchi motor is the can motor used in trucks in low end diesels, and starter set 4-4-2's. The Pittman are the large can motors used primarily in scale sized steam locos.

Thanks!  Any one know when (what series) they switched from AC PullMor to the Pittmans??

right around 2000, when the scale steam craze took hold. When manufacturing went overseas. Some of the last AC motor engines were the NYC Hudson with the Vanderbilt tender, The Commodore 4-6-4 Hudson, and the last run of the 726 made here in the states.

Pittman motor have a backwards history: my understanding is that Mr Pittman manufactured them for model RR use (they were around at least in the early 60's, though the modern "can" version was not; they were open-frame DC's). Turned out that his product was so good that other industries started using them. Usually real-world things get adapted to model use, not the other way around.

I pulled an old computer printer (HP?) apart a few years ago, knowing what was in there. Sure enough: a Pittman can motor, looking for all the world like something out of an MTH/Lionel steamer. It was fine; the rest of the printer was not.

FWIW: Mr Pittman's "DC70" open frame motors were used to upgrade many Mantua HO steam engine motors back in the '60s & '70s. It was a great product line  then and still is IMO.

There are at least eight different motors that I know of, which Lionel has used since the MPC era.  Here's what I remember.  It would be great if @PaperTRW or other authorized service techs with inside knowledge will chime in to confirm or correct this.

1. Small Mabuchi "walnut" can motor.  The first application was mounted transversely in starter set steam locos, beginning with MPC in the late 1970s, and continues to the present day. Ex: NASCAR, Mickey Mouse, Angela Trotta Thomas switcher, etc.  Some have a pronounced cogging effect until broken in; this can be felt by turning the wheels by hand.  The original part number was xx-8008-xxx but I believe that number has now been superseded.  All that I've seen have had a white (earlier) or yellow (current) nylon brush plate.  Very inexpensive; not an especially high-quality motor, and makes for a fast, poorly controlled runner in most of its applications.  Note: I believe this motor was also mounted longitudinally with a worm gear drive, beginning with the redesigned traditional 4-6-2, circa 1996.  That chassis lives on under Thomas the Tank and other locos in the Thomas series, although the motor may have been upgraded to the RS-385.

2. Mabuchi motor mounted transversely in the 2-6-4 (2018-style body) which was re-introduced c. 1986.  Larger than #1 above, with a black nylon brush plate, brass-colored jacket.  Also very subject to cogging until broken in.  A second set of reduction spur gears was added to the 6-wheel chassis in an attempt to tame the high speeds and give better slow speed performance and hauling ability.  The last loco I know of that had this motor/chassis was the Girl's train set engine circa 2001.  The 2012 Girl's Train finally got an AC motor (albeit made in China, similar in concept to the original Pullmor.

3. Igarachi "flat can" motor.  This motor can be distinguished by its oval shape and flat sides.  Brass-colored jacket.  Introduced in the "baby Hudson" (see Ballyhoo Bros. circus set for example)  circa 1998.  I believe this motor was also used in the earliest train set Polar Express; other "baby" Berkshires; the first 0-8-0 train set switchers, and possibly the 0-6-0 docksider.  The same motor may have also been used in the first run of scale 2-6-0 Moguls.  Very small and not a lot of torque.  I consider this an HO-scale motor and light duty for O gauge.  It's largely been superseded by the Mabuchi RS-385, see below.

4. Mabuchi RS-385 can motor.  This is the most widely-used motor in all types of O gauge trains.  Round, dull light grey metal jacket, ventilation holes, 5 pole armature, not skewed.  Generally requires some type of flywheel for coasting in a worm gear drive application.  This is a very inexpensive, low- to medium-quality motor that "gets the job done" because it's often the right size for the available space.  First used in the traditional-sized steam locos: 4-6-2, 4-6-4, introduced in the Korean / Maddox era, circa 1999.  Now used in all of the LionChief Plus steam locos; Legacy B6, 0-8-0, Ten Wheeler, PRR E6 Atlantic, Legacy scale light and heavy Mikados, Legacy K4.  Used in all of the Lionel locos built from K-Line tooling with the motor mounted backwards in the boiler, except the Lima Berkshire.  The newer train set Polar Express locos also have this motor with a VERY tiny flywheel on top.  Although very widely used, an exact replacement must be sourced because the worm gear and/or flywheel are often permanently affixed to the motor shaft.  They would be difficult to remove intact and transfer to a new motor.

5. Mabuchi RS-545 can motor.  Used in the first scale Mikados circa 1992.  This was the first "premium" loco to have a can motor.  (Lionel reverted to the Pullmor in its big scale PRR 6-8-6 Turbine the next year.)  The RS-545 is a mid-priced, medium to large sized Mabuchi motor and definitely not as good as the later Pittman and Canon motors.  The original Mikados can easily be upgraded to a Pittman 9434 motor, as that's how Lionel made them in the early 2000s.

6. Pittman 9434 12-volt.  Large round can motor, brass-colored jacket, 7-pole skewed armature.  Used in the first "premium" scale steam locos made in Korea during the Maddox era circa 2000.  Examples: the much contested N&W Class A, 28072 scale Hudson, B&O EM-1, Century Club Niagara, etc.

6a. Pittman 9434 15.1V  Circa 2004, Lionel reportedly worked with the engineers at Pittman to optimize their can motor design and tame the much-maligned "Odyssey lurch."  The result was a slightly higher voltage winding of 15.1 volts instead of 12V.  In theory this motor should give smoother starting and a more muted top speed.  [The real solution to the lurch, IMO, was back-driveable gearing, which appeared in conjunction with Legacy / Odyssey II circa 2007.]  Used in the scale Berkshires c. 2004, scale Mikados from the mid-2000s, etc. 

7. Buehler dual-shaft motor.  Used in the Vision line Hudson, PRR CC2 0-8-8-0, probably the Virginian 2-10-10-2, and the 2010 issue Berkshires 11203 and 11212.  A dual shaft motor with two flywheels.  Definitely a 'premium' motor, at least as smooth as the Pittman, if a bit smaller.  I've heard accounts of it being prone to burning out in the Vision CC2 application.  Only a few locos circa 2010 had this motor.  The dual-shaft configuration is unique and finding an exact replacement could be problematic.

8. Canon FN-38. Used in almost all of the larger Legacy steam locos from about 2010 onward.  A higher-rpm motor than the Pittmans that preceded it; tends to be paired with a back-drivable idler gearbox having numerically higher (slower) ratios than were used with the direct-drive Pittmans in the early 2000s.  A very smooth premium motor that's a little smaller and lower priced than the Pittman and Buehler motors.  Widely used in O gauge, and still being used as of this writing (2019.)