MTH PCC Trolley Direction Lockout

Your best bet is to download the manual from mth.  It has been so long I have forgotten how to do this but I need the opposite, I need to restore reversing.

From my MTH Railking PCC Street Car manual:

To lock engine into forward or reverse, use the transformer throttle to enter forward or reverse (whichever state you want to lock the engine into) and while the engine is moving press and hold the whistle button. WHILE THE HORN IS BLOWING TURN THE THROTTLE OFF AND THEN LET GO OF THE WHISTLE BUTTON. After about one second you will hear a short horn blast. QUICKLY TURN THE THROTTLE BACK ON AGAIN. Your engine is now locked into forward or reverse and it will remain so until you unlock the engine, even if you wait a year to run your engine again.

Unlocking is the same up to LET(ing) GO OF THE WHISTLE BUTTON. After three seconds without power you will hear one chime of the RESET bell. TURN ON THE POWER AGAIN. Your engine is now in RESET and will operate normally once you interrupt power and enter the forward direction.

Thanks for the update.  Have to try this.  To be clear, to unlock the steps should be have pcc moving, blow horn, DO NOT LET GO, listen for chime, turn power back on?  

Thanks for the info guys. I downloaded the manual as suggested.  I bought the trollies at a train show and they did not have the paper with them.  I am using a Lionel postwar transformer so I will take them to my local hobby shop and ask the proprietor to lock them out for me.