AF 740 Handcar

[irontooth]

Hello everyone, I have a AF 740 Handcar that I have cleaned, put in rebuilt armature and can not get it to run. When I apply power to the car you can see the armature start to turn but does not. The armature turns freely by hand can not see any binding. Anyone got any suggestions????

Thanks

Irontooth

[cwburfle]

Maybe you have a dud armature. I suggest checking each segment against the shaft, and each pair of segments. There should be no circuit between any segment and the shaft. The resistance between any two segments should be the same.

I guess the field could be bad too. Check the resistance of the field.

[lionelsoni]

Are the brushes and the field winding wired in series (right) or parallel (wrong)?

[irontooth]

The field and armature read 3.2 Ohms each (correct by Mr. Hannon's book), armature segments are not grounded out to shaft. It is wired in series (been thru that issue before and learned the correct way) The armature wants to turn when power is applied but stops, could the shaft be to loose in the chassis ways to much play up and down and sideways?  This just has me puzzled, It would have been nice if AF would have put bearings on the handcar shaft.

 

Happy 4th of July

Irontooth 

[lionelsoni]

Do you have a way to try to power it with DC, perhaps a 12-volt car battery?  A possibility is that there is a shorted turn, in either the field or the armature windings.  Having one or two turns shorted may have only a tiny effect on DC resistance measurements, but make a big difference to the AC impedance.  This universal motor should run on DC almost normally even if it has a shorted turn.

[rrlineman]

make sure the field is centered and the straps and gear bracket assy are tight. if the field is off center or loose,the armature will spin but as soon as power is on the field is pulled against the armature.

[irontooth]

I want to thank everyone for the help and suggestions on the AF 740 handcar. I checked the field alignment and the handcar runs now. I did not realize that the handcar fiel s were that touchy about position.

Thanks

 

Irontooth

P.S. Thanks rrlineman for the help

[rrlineman]

you're welcome. that is one of the problems with the handcar. wait till the gear axle holes get so worn it locks ups and overheats. thats a lot of fun.!