We too wound up using a readily available ceramic socket as an interim repair with the same diameter problem that Dale described. Because it's temporary, hopefully not in an archeological time sense, the ceramic socket was wrapped with Scotch 69, high temperature glass tape that serves as a bushing for a tight, secure fit.

The lamp holder used by 1954 on the ALCO S4 isn't adjustable in the reflector. The socket simply slides into what seems to be a die cast sleeve. The sleeve is made to tightly retain the socket by a slip fit and machine screws. The sleeve and the proprietary Pyle National LS10H socket were obviously designed as a mated pair creating this repair/restoration challenge.

The greater issue, we think, for replacing a socket that has 'cooked', carbonized and tracked across the plastic, isn't making a replacement shell but salvaging/finding/making the stamped and formed metal parts that are formed and assembled into it.

Maybe the lesson here is some preventive maintenance, perhaps using epoxy coatings to salvage a thermally aged, cracked Bakelite shell before it tracks.

From a serviceability standpoint alone, I now see why operators were quick to upgrade to sealed beam lamps.

About using the ubiquitous EMD 8237656 socket: although its rough service, I think, silicone rubber for vibration, heat and corrosion resistance, it's probably not rated for headlight service power levels, usually 660W, 250V . That could be a problem even with the typical 300W, 34V headlight lamp, long term. Someone's experience here would be helpful.

You are overthinking this.

In the 'real railroad world', this repair would be made by locating something readily available ( in the storeroom) that would 'do the job' (in this case, light the lamp) and ultimately enable the locomotive to be released for service-quickly.

DPK

While I can quite agree with NH0401's opinion of get it on the road, I would like to restore this as close as possible. I don't know how to mold bakelite. And I will take the old socket and store it in the headlight. I know, not the best location. But if I put it anywhere else, it is lost to the ages, even with a tag.

I would like to make/mold a socket where I can use the original metal parts of the old socket. It is a quest.

Dale