Question on greasing motors

I’ve recently come across a few cars, both hydraulic and traction, where the the front, back, or both ends of the motor have multiple zerk fittings, but no drain plugs. Most of the fittings I’ve seen are painted over (from the manufacturer), are not new jobs, and don’t appear to ever have been greased. I’m wondering if I do try to grease these fittings, if I would be at risk of blowing a seal since there’s no way of relieving pressure. Is this safe to grease without removing one of the zerk fittings? Are these fittings not intended to be used?

I've seen old 1960s machines with grease zerks and drain plugs and brand new machines with both. I've also seen tons of old and new motors with no drain or pressure relief plug that does have a zerk intended to be used to grease it. Rope sheaves can be found either way too.

If the manufacturer is still around I'd try reaching out to them just to check. But generally they designed it the way they did on purpose and the seal or shield on the bearing will let the excess expel out. I would just be cautious and use a little instead of alot.

Just as important as removing the drain or vent plug when there is one, is not mixing incompatible greases. I use a shearstable polyurea grease as it is compatible with pretty much everything (everything commonly sold that might have been used before). Its the green Lucas extended life grease, I have found its the best performing grease I've tried. Unless a specific grease is specified by the manufacturer.

Just my thoughts 41 years in elevator trade and 51 in farming. Grease is better and cheaper than no grease. just 5 pumps in each,,,
each year and youll be fine.

Thank you, that’s really helpful!

Worm is correct a little every year in everything! Grease is cheap. You don’t have to hang a chain block to grease. But you sure will if you don’t