This may be long but worth it.
Picked up a junk Lionel 253 with swollen wheels bad pickup assembly and a chassis that needed a replacement for $15.00 a train show(Price started at $45.00 the it was being dropped every time passed the table. Any way this post is about replacing the contact assembly, using the old Lionel badge and a modification of the contact assembly that there will always be connection between the motor and pickup assembly. Standard practice is to solder the wire to the rivet but over the years the contact fails and the typical solution was to solder the rivet to the pickup on the outside of the pickup causing it to look like a bad repair.
Broken pick up assembly.
Note wire soldered to the rivet.
Picture of the fiber board and pickup assembly. Note there is about a 1/8 hole drilled in the fiber board. Also on the underside of the pickup, I tinned this pickup with solder. The dot represent where the new hole in the fiber board is. When drilling the location of the hole make sure that there is no interference with the motor or axle where the wire would be.
Parts needed for assembling the pickup assembly.
Once the rivets are attacked, uses a soldering Irion to fill the new hole with solder make sure there is enough heat that the solder bonds to the contact assembly. The wire I use a super flex 20 awg strainded wire. It has a silicone jacket and about 120 strands for the wire, very flexible.
Bottom side of the finished pick up assembly with original badge. Note it is a god idea to align the fiber board slots to the slots of the motor frame as a little filling may be necessary for them to fit. It will make your life easier when installing the pickup in the frame of the motor.
This is what I use for speeding the frame to remove and install a the pickup assembly, called expanding plies (not snap ring pliers). Cost about $20.00
Name on pliers STURDYBILT EP-110.