Stan,
I just got back upstairs from testing in command mode, starting from 12v and the speed on the engine set to 4 SMPH on the remote. Engine is stalled, lights flickering, and I could hear the can motor armatures buzzing, not a good thing. I crept the juice up to approx. 13.v, it started to crawl very slow and steady (less than 1 SMPH from the looks of it) and it remained that way, maybe speeding up to approx 1 SMPH as the voltage increased but remaining steady up 17.5v. This entire time, the lights were dim or flickering. Once I hit 18v and higher, the engine took off like a jackrabbit and then resumed it's original surging symptoms.
I repeated the same tests a few times, this time adjusting the engine speed on the remote higher for each one (10 SMPH, 20, and so on). Each time, from 12v up to approx. 17.5v and got the same results as the first test. Some of the subsequent tests the engine kept crawling at ~ 1 SMPH or less through the entire voltage range, even over 20v. If I gave the train a slight push to take up the slack a bit then it would take off quickly for about a foot or so then settle back to it's original surging symptoms again. After this I called it a night so I didn't do the same above in conventional mode.
When it is operating "normally" by not pulling a heavy load or only itself it appears to be pretty close in speed to my other PS2 engines. Early on when I noticed the original symptom I actually did run it for several laps with a couple of other engines with a few feet distance apart from each other and they kept pretty close in speed together from 3-4 SMPH and higher. The problem engine certainly didn't display any behavior indicating it was way off. Same if I had a full heavy train on the other engines and ran it by itself.
So what do you think based on above?
