The is a follow-up of sorts to yesterday’s post about a very nerve-wracking repair I had to make to one of my most valuble and most fragile vintage T-Jets. To minimize the stress of having to work with a compromised body, I elected to get that car back on the track by just swapping out the chassis, although mid-way through the procedure, I found a problem with the replacement chassis that caused me to change course: specifically, I elected to pull the motor from the planned replacement chassis and install it in the original chassis the car was mounted on. That worked out OK and I’m happy to say my ‘63 Galaxie police car is back to hunting speeders on the HO Highway, but there’s still a failed motor to fix!
The motor that failed was a good one, a type referred to my most T-Jet afficiados as an “X-mas tree” or sometimes as a “Tri-Color,” with windings in gold/green/red (to be honest, I could be wrong: the “X-mas tree” may be what collectors call the motors with 2 red and 1 green windings without the gold…but you get the idea). It was installed in a closed-rivet pan, and since the replacement I bought for the Galaxie police cruiser was also an early closed-rivet model, that kept it “correct.” As it turned out, I had to tackle not one but two problems with this repair, because both the motor and the replacement chassis pan had an issue.
For the pan, the problem was the electrodes: the ends of the copper pieces riveted to the bottom of the chassis pan that the pick-up shoes connect to at the big end and transmit the power from the track rails to the brushes. Any T-Jet racer knows that monkeying with these is a dangerous prospect, especially with older, high-mileage cars when they’ve already been “monkeyed with” by who knows how many previous owners. The ends of the electrodes are flexible to a point, but they will only take so much bending over time before they lose their tensile strength and, if bent back forth one too many times, can break off completely, leaving you with an essentially worthless chassis. Yet, adjusting these pieces of paper-thin copper is often essential to getting the right performance for your car, especially if they are mal-adjusted at the outset.
As for the motor: the problem here was what I call the “gear slippage” issue: this is when either the front or the rear gears in the gear train begins to slip on its metal shaft. Once this starts, even if it is just slight at first, it will just keep getting worse until the motor may spin, but the car won’t run at all. Fixing this condition is very difficult unless you have the proper tools; with the proper tools, it’s not hard at all, but the burning question is, what is the proper tool, and how do you obtain one?
In this video, you’ll see a close-up example of how to use the Thunderjet gear press and peening tool! While at the end of the video I indicate that I do not recall where I obtained this tool years ago – I know I bought on it ebay but I cannot recall the vendor – I have seen a tool identical or similar to it for sale from Harden Creek Slot Cars in FL, Wizzard High Peformance in PA, and Scale Engineering in MN, as well as from JAG Hobbies in OH, which I mention in the video. At various times over my 5.5 years of Thunderjetting, I’ve bought supplies from all these vendors, and they are worth a look for tools and parts.
So check out the procedure and then try your hand at it yourself: armed with the right stuff, you’ll be a Thunderjet rebuild expert in no time!
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