Introduced: circa 1969
These little guys are pretty interesting looking models, but unfortunately they just don't run particularly well (more on that in a moment). They had various importers back in the early days of N scale (AHM and PMI most noteably). According to Paul Graf, Atlas also imported them for a brief period of time (circa 1970), but quickly dropped them due to slow sales. Although sold ala carte, they were probably most commonly sold as the motive power portion of cheapie AHM train sets. Circa 1992, Lima's entire line of North American models was discontinued when Lima was purchased by Rivarossi (although this particular model may have been retired well before then).
The mechanism design is a fairly primitive one (featuring Lima's accursed "pancake motor" - a notoriously unreliable piece of electronic junk) -
The pilot truck and 3 drivers pick up one rail (transferred to the frame via springs that are prone to getting squashed down and losing their contact), while the trailing truck picks up the other rail. A non-directional headlight is mounted to the front of the chassis. A Rapido-style coupler is mounted to a long drawbar that screws into the same hole as the tender truck (there is no coupler on the pilot). All six drivers are geared. The motor and all that ugly gearing are clearly visible under (and in) the cab.
I don't know if it's because they didn't age well or if they were simply cursed from the get-go by their bad design. But whatever the case, the mechanism is prone to binding, the aforementioned pancake motor is a joke and the pickup is horrendous. As such, it's nearly impossible to find one of these in working condition. They show up often enough on eBay, but 90% of them are DOA. Sadly, the ones that do kinda/sorta "run" often sell for in excess of $50. This despite the fact that these locomotives are, for the most part, another example of Lima dreck. And be careful when purchasing these used - in addition to not running at all, 90% of them seem to be missing their bells as well.
OK, having said all that, I did actually manage to acquire one of these that runs pretty well. It came in a "brand new" (IE, never opened) AHM trainset. And believe it or not, it actually runs like a good (well, mediocre anyway) trainset loco should. No, slow speed performance isn't there, and it couldn't make its way through a turnout to save its life. But give it some throttle and a simple circle of track and it actually runs around fairly smoothly and quietly. So, I guess it's at least possible to find one of these things that actually runs. Unfortunately, the odds are not in your favor. I'd say I've looked at at least 20 of these things over the years, and only found the one that ran worth a darn.
Trivia - AHM/Lima marketed this model as a "camelback", which I guess is totally wrong. I'm told that it's actually a rough representation of a Reading 2-6-4T suburban tank engine that was used prior to electrification of the Reading's suburban services out of Philadelphia in 1930. A couple of US railroads (Boston & Albany and CNJ) continued to use these into the 1950's, and the CN used them in suburban service out of Montreal until the late 1960's.
To remove the shell, first remove the screw that holds the pilot truck to the chassis (see below). Next, remove the small metal tab that provides downward pressure on said pilot truck. This will then reveal the small screw that holds the shell to the chassis. Once this second screw has been removed, the shell should come off fairly readily.
Grade: C (if you can find one that runs at all)
Here's one still happily tucked away in its box:
And here's one lurking in an AHM train set: