Bought it on eBay, converted to battery/RC
Runs for maybe 5 minutes then slows and stops. Motor is quite hot.
Feels like a stall to me… But what?
I finally got some lube and applied gear lube to the worm and pinion drive gear, and light oil to the axles.
Should I lube the motor too? Is there another likely cause or area of binding?
Thanks…
Michael
Did you remove all the track pickups in the motor block?
What kind of power are you running it on? Many small, inexpensive DC motors don’t like the very low frequency PWM power such as found in low cost PWM controllers. The most noticeable indications are noise and overheating.
If on pure DC, how much current is it drawing? If more than 1 amp, either something is binding or the motor is defective. The Bachmann Big Haulers I have measured all draw around 0.5 to 0.7A at max (read warp speed) voltage.
Lubricating the motor bearings is okay, but I seriously doubt the motor bearings have enough friction to overheat the motor. Keep your lubricants off the motor brushes and commutator.
Happy RRing,
Jerry
I have not removed any track pickups, so that is something to do, of course.
I am running off a 14.4V NiMH battery driven by a Pololu motor controller and a 22khz PWM frequency. Does that seem like a problem?
I’ll check the current draw. Right now (apart from the track pickups) my biggest suspect is that the drive gear’s old residue is sticky, and some good ol’ detergent is in order.
Thanks for the hints!
Take off the bottom of the motor block. You will see some long wires/brass strips, as I recall, been awhille, that touch the axles. If you do not remove them, cut the wires, your battery is feeding it’s power through the motor to the rails.
Michael:
Sounds like a good setup. The low frequency PWM controllers I mentioned run in the 100 to 1000Hz range. Yours running at 22KHz should not be any problem.
Do remove the pickups. I was thinking that since the locomotive was designed to ‘drag’ the pickups when track powered that couldn’t be the problem, but Jerry Barnes’ suggestion about drawing power through the motor makes good sense.
Cleaning / lubricating is always good. Just really hard to believe there is that much friction in the motor / gear train, but anything is possible.
Testing the current draw with the motor powered from a clean DC source would seem to be the next diagnostic step.
It almost sounds as if the motor has an internal problem, but I would think you would notice something like a shorted winding in either the starting ability or in the maximum speed.
Please let us know what you find, as there are lots of Big Haulers out there, with a few that occasionally don’t work. Usually very reliable locomotives, but there’s always an odd one that defies trouble shooting attempts. If it does turn out to be a duff motor, they are readily available from B’mann.
BTW, my (technically challenged) neighbor’s Big Hauler arrived with two wires crossed (with the insulation cut through) under a screw that held the chassis on. Made a direct short in the power wires from the lead truck to the motor. Took me several tries to locate the problem, but a small piece of tape fixed it. For a while, I was thinking his grandson was going to have a push toy on Christmas morning!!
Happy RRing,
Jerry
Update (and thanks for the suggestions)
So, while there may have been too much friction, it appears that the new charger is not working. So, weak battery drawn down by a load was stopping the motor [edit: at 10V, I had the controller set to shut down]. I was reading the light wrong on the charger. I have a query in to the sellers.
Thanks for the help and suggestions!
Michael:
Glad you found a correctable problem, but now I’m confused.
Low voltage = Low current, so what is causing the motor overheating?
Inquiring minds want to know!!
Happy RRing,
Jerry
Michael Moradzadeh said:Every track powered Big Hauler I've ever seen has two brass strips running from axle to axle for power pick-ups. As Jerry Barnes stated, you have to remove the engine cover to get to them. If you didn't remove these brass strips, they are likely drawing power off to the track. Ralph
2. There are no pickups, only a couple of wires from the front truck (already clipped for now)
My best guess is that I was suffering from a combination of too much friction and a battery on the edge. I’ll have a better sense when I address the charger issue. I’m thinking that the hot motor was from cycling it with the low voltage limiter kicking in and out but the motor stalled from friction.
As to the strips, well, I’ve had the motor cover off and the bottom plate out and the wheels out. No strips. There’s a couple of contacts on the forward axle that trigger the chuff sound (one contact closure every half revolution), but no axle strips. In any event, I am running on plastic track right now, so while controlling where power might be flowing is an issue, it is not an immediate issue.
The wiring diagram I have found online is for a different setup, with power running to the tender. Mine does not have that, and there are other differences…
Research continues.
George Sheyers has a tips page for everything big hauler, among other things.
http://www.trainweb.org/girr/tips/tips1/big_hauler_tips.html#gears
I used his soundbard tips and run them with very good results.
Thanks for the link. I had run across that before, and was looking for it. Great advice there.