I'm having trouble with a Kato SD40 I just picked up. It is an early release (has the 8 pin DCC socket and yellow diode lights). I can't get power to the motor consistently. There seems to be a problem with the copper strips that run from front trucks to rear trucks on one side. At first I thought the spot "welded" copper lead that went up to the circuit board was the problem - it didn't seem like there was a good connection - so I soldered it together. That didn't fix the problem - now it seems to work fine with no body shell but when you push down the body shell, you can knock out power to the motor (lights still work, can switch from front to rear lights, etc.). If I fiddle with the side of the engine along its side, I can get it to run for a while, then it quits again. The engine is different from my other Katos as the copper strips from the trucks are exposed. Anyone had a similar problem? Anyone found a solution or can anyone recommend a solution?