Anyone who knows how maintain a generator (electric)?

Question

is there any maintenance procedure on it?

Answer 1

Maintenance? We're supposed to do maintenance on those things?

But seriously, the maintenance required really depends on the type of generator and the source of energy that spins the generator.
Wind turbine
Steam turbine
Hydro
Natural gas or gasoline reciprocating engine
etc.

Spinning parts have bearings that generally need lubrication.

You'll need to furnish more details regarding the size/type of generator.

Answer 2

I'll assume you are inquiring about a home-size stand-by generator or a motor-home unit! I'll further assume you are concerned with a gasoline-engine driven unit! Like an automobile-- check the oil level in the crankcase of the engine maybe every 3rd month unless you are running it frequently in which case, check it each time you refill the fuel tank; keep gas-stabilizer in the fuel unless you are running it steadily; run the thing once a month (5 to 10 minutes) whether you need the power or not! There should not be any maintainence points on the generator itself! Twice a year check all screws and nuts, except those on the carburettor, to make sure they are still tight (including all electrical connection fasteners)!