# T-Jet 500 motor repairs



## tzavitz (Feb 14, 2019)

I have several 1960's-70's Aurora Thunderjet 500 HO slot cars. While the motors work, they run much slower than when they were new (and I was young!). What can I do to recover the speed that they should have? Is it the magnets getting weaker? I've cleaned and lubricated all the motors, but they just are slow. If it's the magnets, is there a way to "charge them up"? Your advice is appreciated.


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## alpink (Aug 22, 2010)

magnets can be zapped back to original strength. 
but, for what that costs you can get aftermarket magnets on eBay and some from current manufacturers ... Auto World ....
you also need to get new commutator brushes. the used ones are too worn to give good performance.
if you make those changes and they are still slow you need to check for bent axles and binding.


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## tzavitz (Feb 14, 2019)

So it IS about the magnets and the brushes.....any worries about the commutator/armature? How does one test these with a multimeter to make sure they are ok as well?


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## Rich Dumas (Sep 3, 2008)

In my experience ceramic magnets hold their charge very well, it is unlikely that they have lost any strength. Newer magnets, like the ones used in Johnny Lightning or Auto World cars are considerably stronger than the ones in Aurora T-Jets. It is likely that your motor brushes are worn down and need to be replaced, you would be better off using the ones by Slottech or Wizzard. It would not hurt to shine up the commutator with a little metal polish. Possibly the pickup shoes are worn down or need to be adjusted. T-Jets have a lot of gears, make sure that there is not any lint or hair wrapped around the axles and that everything turns smoothly. Finally T-Jets are fussy about oil, the lower end of the motor shaft is an especially critical location. Excess oil there will get on the motor brushes, coat the commutator and slow the car down, so only a tiny drop is needed. If it runs dry the car will really slow down and will often make a squeaking sound. If you persist in running the car it might burn up. Almost any sort of oil will work, but some kinds will work a lot longer. I use Superlube from Slot Car Corner.
You might take a look at this article: https://drive.google.com/file/d/1msYjFT2HVbaSxNC5g_QhEwM8cjBHyDNf/view?usp=sharing


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