12767 Steam Clean And Wheel Grind Shop
Wheel Grinder Circuit Repair
The Floodlight Tower and Control Panel lights were out on
the Wheel Grind section. Inspection revealed a melted
Lamp Adapter inside the control panel. The circuit board appeared to
have a damaged bipolar transistor, capacitor and the 16V lamp
adapter .
Electronics component identification required a consultation with my
electronics engineer (my son Brad). The following components
were replaced.
 |
Upgraded Bipolar Transistor The reference numbers refer to the connection positions in red on the circuit board photos with the schematic pdf. |
 |
The damaged
capacitor between the motor leads was a 0.1uF Ceramic-Disk
Capacitor 50WVDS maximum (High K dielectric). Radio Shack part #272-0135 Pkg. of 2 Yes, Radio Shack stores are still open as of June 2016. |
See melted adapter circled in red.
The socket with red and white leads was undamaged. |
Upgraded to
18V / CLEAR LAMP Adapter with 16V Lamp Installed  Lionel Illustration and Part # for Floodlight Tower Lamps |
See Brad's circuit schematic and component connection photos.
Parts List of Circuit Board Components Replaced
Q2 (TO-92 case) Bipolar Transistor - BJT
NPN/40V/1.5A
Fairchild Semiconductor #SS8050BBU or Radio
Shack part #276-2009
C4 0.1uF Ceramic-Disk Capacitor 50WVDS
maximum (High K dielectric).
Radio Shack part #272-0135 Pkg. of 2
Lamp1 Lionel #620-5100-300 LAMP / 18V
/ CLEAR / W/ADAPTER (The higher voltage may prevent a future
melt.)
(Lionel lists an original 12V 70MA lamp for the control
panel.)
Parts List of Possible Circuit Board Components to Replace
Q1 (TO-220 case NPN silicon)) original #
99227 TIP31A
Central Semiconductor part #TIP31 Bipolar Transistor -
BJT NPN Gen Purp Power
Radio Shack part #276-2017 (not replaced)
D1 Zener Diode 12V 1W ZENER 5% Fairchild Semiconductor # 1N4742ATR (not replaced)
Motor and Flint for Spark Generation
Lionel Replacement Flint is Part #610-2767-111. The replacement motor is listed as unavailable.
A possible motor replacement is Mabuchi FK-280 Motor - 10 to 15 VDC - Model Train Motor
 |
 |
 |
 |
Go to Wheel Grinder Assembly
Return to Operating Cars and Accessories