G scale Rail truck

[The Scotsman]

Can anyone help me identify the Q7 and Q8 type of transistors on the PC board of the rail track, they are   the two closest to the back of the board, mine got scorched, I think the numbers may be A1300 and GB201 but I'm not sure. I also ran into the oddest problem with the motor, the motor would not run unless it was turned upside down, a brush or spring problem? Anyway I replaced the motor and everything seemed to run well until I assembled the truck now it wont run on the track, the motor runs, but nothing else. Any advise? Thanks in advance.

[ricnpat]

Sounds like a cracked gear.
Pull the cab and floor boards and check the  gear in the "transmission"