Connie Outside frame current draw

[davepenn7]

I recently replaced a damaged non driving wheel set on my Connie. Loco worked OK without any cars attached, although it didn't appear the loco was pulling much current. When I attached several heavy cars the loco wasn't able to pull these cars and again no indication it was drawing any current. Any idea what is wrong?

[Kevin Strong]

The loco runs fine with a light load, but stalls on a heavy load? When it stalls, you say it's not drawing any current, which doesn't make sense. If the motor is stalled under a load, the motor should be drawing "stall current. If it's not drawing any current, then it's not getting any power.

Later,

K

[Loco Bill Canelos]

Hi davepenn7,

I am wondering if in some way when you reassembled things you created a short in some way?  Did the loco come to a complete stop when pulling the cars?  Did the headlight go out completely or was it just dim?  Did the power supply shut down or indicate a short of any kind?  When running without the cars and the power pack run at full speed did the headlight dim or stay bright?  Please state what power supply you are using and the amp rating on it?  You may well be using an underpowered power supply, but hard to say.

It is tough to diagnose this kind of problem without being there, so I am not sure I can help, but I will try.

Loco Bill

[Greg Elmassian]

Any progress on this issue?

[armorsmith]

Dave,

Late to the party, but let me get a better understanding of the situation. First, is this a purchase you made brand new or is this a second hand purchase? This matters so I can understand whether this was a running locomotive you already owned or is a second hand that you are attempting to repair with only the known damage of one driver set. I am understanding from the track of the thread that the driver set you replaced is NOT on the motor driven axle.

Could you clarify your statement "Loco worked OK without any cars attached, although it didn't appear the loco was pulling much current." Can you provide the current you measured?

"When I attached several heavy cars the loco wasn't able to pull these cars and again no indication it was drawing any current.", does this statement mean it was the same reading as above or was it zero?

From your description it is my opinion that the axle gear on the main drive axle is cracked. Bachmann used a pressed on gear, which when they cracked would present a variety of symptoms from outright no motion at all to a sputtering to similar to what you are describing, etc.

Amperage draw can be a tell tale. If the gear is cracked but holding on by a thread, enough to move the locomotive with no load, you will get a given amperage draw which will be near a 'no load' amperage on the motor. When you add the additional load of several cars, this overcomes the frictional ability of the cracked gear and it slips. When you  check the amperage, it will be very near or the same as the loco with no load because the motor is not driving anything, just spinning and turning a set of gears that are not driving anything.

I have replaced three of the offending axle gears, but it has been awhile since I have done them and don't want to foul up a description on how to do it. I hope Loco Bill will chime in with a link to the article/thread on how to. This will get you to where you can inspect the axle gear and determine if it is the offending item. Again it has been awhile but Bachmann at one time was selling replacement axles with brass gears which has fixed all the issues I had.

I also find it interesting how two readers of your OP interpreted the presented query differently.  I hope my reply will be of help in restoring your Connie to functioning condition.