Lionel legacy sw2 Switcher loses sound when going over switches or bumps.

First thing to check is continuity between the two roller sets, and then the wheels on the two trucks.  If one isn't carrying power to the PCB, that would certainly cause the issue.

If the rollers and wheels are all connected, then I'd say it's perhaps dirty wheels/rollers or the like.  Clean them and the track.

Finally, if all else fails, consider adding the YLB - RailSounds Battery Replacement (RS-Lite) to eliminate brief power drops to the sound board.

GRJ - can the RS - Lite be added to a conventional Lionel engine with sound but no battery backup to keep the sounds going during direction changes?

Ron

Seems like I saw that even conventional engines with out the battery connector wire still have a 2 pin connector on the PCB board to add a pigtail.

@RON ARNDT 091718 posted:

GRJ - can the RS - Lite be added to a conventional Lionel engine with sound but no battery backup to keep the sounds going during direction changes?

Sure, you'd probably use the other model with the battery clip: YLB - RailSounds Battery Replacement

Note the two versions, the circled connectors are the only difference.  The left one is for RailSounds that has a battery cable with clip, the right one is for RS-Lite boards like are supplied in many Legacy locomotives and also in the ERR RailSounds Commander upgrade kits.

@cjack posted:

Seems like I saw that even conventional engines with out the battery connector wire still have a 2 pin connector on the PCB board to add a pigtail.

All except for the latest Legacy stuff.  The new 10-wheelers and Camelback that I just got dispensed with the battery connector!   Wouldn't you know it, all of them exhibited a problem going over my double-slip switches and the sound would drop out and restart!

I worked out a fix for the newest RSL4 board they started using, it's in all three of my new locomotives with the new sound board.

New Legacy Steam Locomotive Sound Issue and Fix

Thank you very much for all the great information.

Jerry

How everyone. I tried cleaning everything and I still lose sound and sometimes power when when going over a certain track suction and some switches. I was going to add a 9-volt battery per the instructions but I cannot find the battery connector? Any suggestions thank you very much, Jerry

The battery will do nothing for losing power, you have to find the reason for that happening and correct it. I'd start at the center rail rollers and then move to the wheels and see if you have poor continuity somewhere.

The battery ONLY keeps the sound going during brief power interruptions and for conventional operation.  For diesels, I normally only consider a battery if it's going to run in conventional mode.

Can you post a picture of the track in question ?  Usually with 4 pickup rollers [all with springs]  finding the center rail isn’t usually an issue. You mentioned the track is bumpy. With traction tires only 4 out of the 8 wheels make good electrical contact. It’s important the wheels are squeaky clean and all the outside rails have power drops. This problem area may only effect this 1 engine. Check the rails and if the track is bumpy maybe try adding shims to level it out.

I had a Legacy 0-8-0 that would stall when changing direction on a straight 3 ft. Section of Gargraves. A twitch of the engine always brought it back to life. 2 traction tires, 4 blind drivers and only 2 for a good electrical path. Added a jumper wire between the engine and tender that connected the 2 chassis’ together and the problem went away. The latest 0-8-0’s added a tether to solve it.

When I owned this same loco, certain operating track sections would cause the pickup roller to rise and make contact with the underside frame of the unit, and thus, short out.

I applied some black electrical tape to that area of the frame and it eliminated the issue.

Thank you for your answer. Never thought of that. I have it running pretty good now but will look into the tape can add it. Thanks again, Jerry