MTH Battery

The model in your picture is an MTH Premier Lehigh and New England Alco S-2 diesel #613 (20-2614-1) with PS2. To access the battery and electronics on an MTH diesel, you need to remove the upper body from the chassis. Body is usually secured by four screws - two at front underside of chassis - two more at rear.

Reinstall the screws you removed from the fuel tank. They won't lead you to the battery.

MELGAR

I'm guessing the four screws you removed are to hold the speaker in place. These screws look like they would actually remove the fuel tank:

The online manual doesn't have clear photos but this should help:

From your photo, here are two of the four body mount tabs referred to in the manual:

FWIW, on other MTH diesels, two of the four screws in the fuel tank DO hold the car body and must be removed to take the car body off to access the battery and other innards, in addition to the other four screws at front and rear.

Thanks for the tips and suggestions.  Part of my befuddlement was due to running a search on YouTube for a video to follow and finding something close but not exactly correct as far as engine type.

I assume to get at the battery in the S-2 I will need to remove the trucks to have access to the body screws.

Is there a way to easily tell what kind of battery I need for a locomotive before I disassemble so I only have to open it once?   I understand that there are two different batteries.

Besides two S-2s I have the following locos that I may want to replace the batteries:

Reading 635  30-2425-1

Pennsy 8974  30-2379-0 or maybe 1

Jersey Central FM 2408  30-2928-1

LNE Camelback 153 30-1402-1

Many thanks.

@JPS posted:

Thanks for the tips and suggestions.  Part of my befuddlement was due to running a search on YouTube for a video to follow and finding something close but not exactly correct as far as engine type.

I assume to get at the battery in the S-2 I will need to remove the trucks to have access to the body screws.

Is there a way to easily tell what kind of battery I need for a locomotive before I disassemble so I only have to open it once?   I understand that there are two different batteries.

Besides two S-2s I have the following locos that I may want to replace the batteries:

Reading 635  30-2425-1

Pennsy 8974  30-2379-0 or maybe 1

Jersey Central FM 2408  30-2928-1

LNE Camelback 153 30-1402-1

Many thanks.

Look at the bottom of the locomotive for the charging port. If it is a round connector with a single pin in the middle it's the old 9v style (8.4 NiMH) battery.  If it is a rectangular connector with two pins, it is the newer 2.4 battery pack.

Trucks don't generally come off unless the body is already removed.  According to the manual, there should only be two screws and four body clips that need to be pinched to remove the shell from your S-2.

As a rule of thumb, if shutdown sounds last for 7 seconds, or longer, after power cessation, you don’t need to replace the battery. Of course, if you want to, that’s your decision.

Also consider searching this forum for threads on battery replacement super capacitors. I have not yet done this, but my understanding is that it takes 10-15 seconds for these capacitors to charge when you power up the loco, but you never have to worry about discharged or leaky batteries again. This is on my list to try.

This may not be helpful, but I have an MTH SW-1 that appears to have no battery, just capacitors.