It may not be obvious visually, but a good whiff will tell the story: this is an Auto World Ultra G race motor that expired in a literal blaze of glory
It was almost exactly one year ago (but in some ways it seems like a different life now) that I mentioned that the opening of the 2022 fall racing season had resulted in an explosion of engine fires at the track. Prior to then I had only ever burned out 2 motors over a nearly 3 year period of almost daily racing, but then I lost 3 within a 2-day span. I lowered the voltage from my power supply after that, but even so I’ve still had several more motors expire. Here is the reality: like any other racing car motor, the little pancake armatures in these T-Jets are only going to last so long: the combination of the downforce of neodymium traction magnet with the tremendous speeds demanded by the long straightaways at Drag City are punishing, and even my fastest and best performing cars seem to be reaching the end of their lifespan. Truth is, there probably isn’t a whole lot I can do about it: we don’t race cars to preserve them, and high performance results in high wear and eventually failure. So be it.
The motor fires are hideous, though; there’s the slowing, the smoke, and then the smell hits you, and the smell is awful! Its amazing how pungent it is! And at least one of these failures was so hot that the brushes burned through the recesses in the chassis, ruining the pan as well. No matter how inevitable it may be, this is not something you want to happen!
Its interesting, though, that in almost all cases, these motors will still run once they cool off; they’ll run, but they’ll never been the same again. I’ve only ever had one that failed to the point when it would never come back to life. Knowing that has given me a way to be conservative with parts, and keep everything going.
As I’ve mentioned, a good number of the cars in my vintage Road Crew aren’t really vintage: they are reproductions, and many run on the early versions of the Playing Mantis T-Jet repro chassis, the Johnny Lightning Thunderjet 500. They are identical in every way to the later Auto World and (now) Round 2 T-Jets except that they lack the moly traction magnet. As a result, the motors on these older chassis will swap right over to the newer ones. So, when I found myself with a handful of cars with burned out motors, I turned like a salivating animal to the Road Crew and canabalized those cars, pulling their motors for my racing fleet and swapping in the very burned out motors that had to be retired.
It sounds terrible, but it’s remarkably effective: the burned out motors are not useless; they are no longer capable of racing, but they still have life left in them, and on the low-power, low-speed HO Highway, they run great with the old Aurora cars; in fact, they can still run rings around many of the original cars! The only drawback is that lingering awful smell… Unfortunately some of the older motors aren’t as fast as some of the newer ones, so some of them have been disappointing as substitutes for the racing motors they were swapped in to replace, but I’ve had more that were completely adequate: perhaps not the hottest performers, but still very competitive on the track!
The only bad thing about this plan is that when one of the top performers expires, a replacement Playing Mantis motor may not be adequate. In cases like this, the only option is a complete chassis replacement, and I’ve done that-in some cases more than once. Even so, reusing motors that are no longer fit for the racing track seems to me a lot like a former Olympic track star reaching old age; we don’t euthanize them, no matter how many Malthusians would like to see that; we treat them like aging heroes. The Road Crew gives these former heavy lifters a place to live out the rest of their days doing was they were built to do: running around the track!
I love how you find ways to keep things going and alive at Drag City. Reusing, salvaging, preserving are all great strategies to keep as many of these great machines alive.