Lionel 8769 Republic Switchers. Is it an AC or DC engine please?

DC unit. The motor is connected directly to the track. Recommend CRC 2-26 or contact cleaner to clear out old grease. Grease internal gears with Red 'n Tack #2 or Labelle 106. Lubricate shafts with Labelle 107 or Mobile 1 5W30 synthetic, and external gears with Labelle 102.

That one will reverse for you when you change dc polarity/direction sw. if I'm not mistaken

Try to keep voltage under 12-14v on these little ones too. They usually only need 6-9 to run nice anyhow (if you run into acc. cars needing more voltage, you add an oppsed diode chain on the motor so it needs more track volts to begin to move)

Another DC perk: If you change to led headlights, 2 headlamps automatically work directionally if wired in opposing fashion (2 led/ 2 diode/2 resistors).

Plastic/nylon worm gears on axles are old as post war and later horizontal can motor styles that are made in black delrin and do surprisingly well too. (delrin is a self lubricated plastic and needs no lube. I still oil delrin trucks, but it's for rust protection on the axle tip, not to lube)

However the horizontal motor's derin gear retainers, that hold the 1st gear to the armature gear and wheels or other gear, are a little too thin and can crack if you abuse the design with weight and heavy loads and/or intoduce a hard enough phsical shock against the drivetrain. (this was a nice hard chunky steel retainer on old style designs... to bad they didn't just cast those in delrin instead of whittling away the mass for a ¼ penny saved.) If your frame has one of the horizontal motors I'd get a retainer or two for the parts box for $2-3 while they exist at shops. (& those old dc motors were still only about $10-$15 last I checked a couple years ago)

If I clean it up and it runs fine, does anybody have any idea what its worth?  I tried googling it, and found an old auction sight from years ago, which said that the last one sold went for $50.   That seems insanely high for a plastic, can motor, engine.  So, I don't believe it is correct.

Thanks for you info on cleaning and oiling, and let me please know if you have any value information.

By the way, the wheels on this engine only have one rubber band cover, on the front right hand wheel.  Are there suppose to be more than one rubber covers?

Thanks,

Paul

@Mannyrock, here are the Lionel Service diagrams. Only a single traction tire.

As for value, sold listings on eBay auction site seem to be between $18-$30 for the locomotive. Don't expect much from this little guy. 2 - 3 light cars would be its max.

Wow Moran, thanks.

I'd not seen a horizontal worm & 90° gearbox in a starter set Lionel before. Just horizontal motors, parallel to the axles. 

Is the weak link the traction, the motor, or the gearbox failing? Can it handle more if weighted for traction like some other small can motors, or is a hot motor or weak stall torque or prone to stripping the box? Slipping of the drive gear press on the box? 

I think I want the  motor & gear assembly for a bash if the gearing is of decent strength; I need the 90° offset and don't want to foot the bill for brass; the rpm range isn't even an issue.