Motor problems

[ax-10 crazy]

What would cause a motor to stall out or not start at all until turn manually? I know it is not a hung brush, I have cleaned the motor swapped motors front to rear. Swapped armatures from on can to the other.

Sometimes it will go if voltage is applied (doesn't matter what voltage 4 cell nimh, 3s, 4s), and sometimes it will just stop or spark and have no movement. I have recently installed new brushes and broke them in but it still does the same thing.


Specs:
-XR-10
-brood 40t motors
-dual brxl's

What could my problem be? I know they need a com cut but my lhs doesn't have a motor lathe I don't know if they have anything ever in stock.

Thanks

[EddieO]

If you swapped motors armatures and it's still doing, I can't see it being a motor problem...

If you have not cut the comm a just cleaning them and replacing the brushes will not help with a hung brush 75% of the time. Typically the brush is hanging on a pit in the comm...

But like I said, if you have swapped motors front and rear and the problem still persists, unless you have the exact same problem on both motors....I would say the problem lies some where else.

Have you tried swapping the speedos front to rear? If the problem moves, then the speedo is the problem....

Do you have plugs in the motor circuit? I have found many times that plugs can go bad and mimick a hung brush.

Try the above.....if that doesn't work, we may need to look at the motors.

Later EddieO

[ax-10 crazy]

Originally Posted by EddieO

If you swapped motors armatures and it's still doing, I can't see it being a motor problem...

If you have not cut the comm a just cleaning them and replacing the brushes will not help with a hung brush 75% of the time. Typically the brush is hanging on a pit in the comm...

But like I said, if you have swapped motors front and rear and the problem still persists, unless you have the exact same problem on both motors....I would say the problem lies some where else.

Have you tried swapping the speedos front to rear? If the problem moves, then the speedo is the problem....

Do you have plugs in the motor circuit? I have found many times that plugs can go bad and mimick a hung brush.

Try the above.....if that doesn't work, we may need to look at the motors.

Later EddieO

The motor was out of the truck during testing. It was under direct voltage (4 cell nimh) and would still do it.

I have resoldered the connections and that didn't help.

Thanks for the help

[EddieO]

Two things then...

It's either a hung brush, cut the comm and hopefully the problem takes care of itself. It's possible the comm has already ruined the new brushes again.....so really should put on a new pair as you cut the comm.

If it still does it, then you have a stalled armature........only fix is to replace the arm. Often happens from the motor getting it a nasty bind and drawing excessive amps.

Bit confused on your first post since you said both motors did it, but only in the one spot....

Later EddieO

[ax-10 crazy]

Originally Posted by EddieO

Two things then...

It's either a hung brush, cut the comm and hopefully the problem takes care of itself. It's possible the comm has already ruined the new brushes again.....so really should put on a new pair as you cut the comm.

If it still does it, then you have a stalled armature........only fix is to replace the arm. Often happens from the motor getting it a nasty bind and drawing excessive amps.

Bit confused on your first post since you said both motors did it, but only in the one spot....

Later EddieO

Ok, I guess that narrows it down.

I guess I should have been more clear on my first post, it is only one arm that does it and one motor.

Thanks

[ax-10 crazy]

Would a hung brush cause lots of sparking when throttle/voltage is applied? Or would it be a stalled arm?

Thanks

[JohnRobHolmes]

More likely to be a hung brush or bad timing to cause arcing when throttle is applied. A stalled arm would just have dead spots.

[ax-10 crazy]

Originally Posted by JohnRobHolmes

More likely to be a hung brush or bad timing to cause arcing when throttle is applied. A stalled arm would just have dead spots.

I have no timing on the motor. It usually stops at the same point on the com so I'm thinking it is a stalled arm