If it’s anything like my old 13” there should be 2 oil cups on the headstock, one near each bearing. A little below there would be two 1/8” NPT plugs that can be removed to drain the oil. There’s nothing really that has an oil reservoir per say, the headstock and apron are really the only places that hold oil. Everything else uses oil wicks that rely on the user to ensure the oil is topped off on them.
The motor probably needs to be rewound if it’s smoking when plugged in. Is that happening before you turn the switch on? Are you running the correct voltage for the motor? Did it come with a plug on it or was it bare wire ends and you put the plug on it?
Can’t be much help with the belts if your step pulley is set up for V belts. What style is it? Is the motor under the headstock, behind it, or above it?
Those pictures would help tremendously.
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