SSPRR Run Room

Playing with Toy Trains

UCS-40 and RCS-20 Operating Track Section Controllers


All Lionel Earlier Operating Track Sections are Controlled with the Same Controller.

UCS Controller


Postwar UCS Controller Repair


The most common repairs for postwar controllers are cleaning the contacts and adjusting the springs.

Mark Wires Before Removal
Use tape or 3M Wire Markers in rolls or books.

Remove Controller

After marking wires, remove from track and power bus bar.

Under Table Wires



Log Controller was inspected and serviced in place.
Log Dump Controller
Coal Dump Controller Needed Bench Repair
Coal Dump Car



Place the Controller over a parts tray or clear surface before removing base.  Note broken and loose parts.  The # RCS-27 Spacer Button is a must have.

Remove binding head screw from springs to clean electrical contacts with 240 grit wet or dry paper.

See below for Controller operation.
Loose Spring Contacts

Stack Functions

Refer to Diagram for Reassembly
The track illustrated is Lionel's postwar 027 operating track.
See pdf diagram here for printing.
Before screwing assembly back into case, hold it together and compare to Normal Position in above stack.

Soring Stack Diagram



Spring Adjusting After attaching stack to case, check contact spacing with a strip of index card.

The ST-302 spring adjusting tool is available as a reproduction from toy train parts dealers.  The tool is also used to adjust switch (turnouts) spring contacts.


MPC Era Controller Improvement

   MPC/General Mills era (1970-1986) Lionel Corporation


The MPC redesign resulted in the square shaft breaking off with user's rough treatment.  My experience gluing structural plastic parts has had poor results.  This fix results in a better Controller.
Both Controllers below were improved.  The Controller on the right had the broken square shaft.  The shaft parts were glued together and glue set before improvement.


For Improved Operation
Remove Spring assembly.  Repair square shaft in cover if needed.
Drill 7/64" pilot hole in square shaft from inside of cover to locate outside center.
Drill 1/8" hole for 4-40 screw from outside.
The spring stack diagram below shows the difference from the postwar spacers.

Spring Stack


UCS Controller Improvement Parts (bottom center below)
Black 3/4" 4-40 phillips round head machine screws
18-8 Stainless Steel Hex Nut   Black-Oxide, 4-40 Thread Size
Black Nylon Plastic Washer for Number 4 Screw Size, 0.115" ID, 0.25" OD

MPC Controllers


Improved MPC Controllers with Phillips Head on Top and Black Washer and Nut Inside

Improved Controllers

Reference Documents




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