# 4-6-6-4 DCC/Sound technical conundrum



## fs2k4pilot (Jan 5, 2013)

Guys, I've got a REALLY tough issue with an older Athearn Genesis 4-6-6-4 (ATHG 9122) that I've had a TSU-1000 installed in. Since then, it hasn't had any pulling power in the forward direction. It pushes plenty strongly in reverse, though. To day I put it on my test track with two Bachmann diesels coupled to it (not MU'ed, just coupled) and tried to shove them around. In reverse the engine had no problem, but when moving forward, it chuffed like it was moving quickly, without actually moving quickly (at speed step 20 of 128, it moved as if it were only at step 5, but chuffed at 20).

I've tried factory resets, I've tried setting up the DDE, I've tried NOT setting up the DDE, I've tried maxing out CV's 10 and 212, I've sent it in to the Athearn tech department twice (they installed a new motor this time around), I've even tried reversing the Motor leads and reprogramming CV 29 in the hopes that this would at least reverse the problem if not solve it. I don't think it's a mechanical or gear problem, since it should manifest itself in both directions, in that case, right? I measured the voltage going to the motor in both forward and reverse, and the voltage is the same. Perhaps it could be a defective decoder?

I'm completely buffaloed, and I'd really prefer not to have to write this engine off and get a new one. Anyone have any ideas?


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## Brakeman Jake (Mar 8, 2009)

Have you tried turning the drive shafts manually,no current applied.It seems more like a binding truck than a decoder problem.There may be a broken gear or else that falls in the geartrain going forward and pushed away when backwards.If voltage to the motor is the same in both directions,it should go.Since the motor was replaced,it should be OK.


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## fs2k4pilot (Jan 5, 2013)

It's not a problem with the engine. I hooked the Challenger engine up to the tender and decoder from my Athearn Genesis Big Boy and it had satisfactory performance in both directions. I then hooked up the Challenger's tender to the Big Boy, and it had a noticeable loss of pulling power. Also, I had the guys at Athearn pull the drive train apart and check it last time it went in, and they didn't find anything wrong.


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