The incident occurred this evening after five farmers entered the 60-feet-deep well to install the pump for fetching water for crops.
However, after the pump was switched on it emitted smoke which soon filled the well which has a narrow opening, an official said.
He said three out of five farmers, identified as Babasaheb Wable, his son Rameswhar, and one Arjun Dhande died on the spot, while two others fell unconscious.
Farmers typically run the motor engines using kerosene or diesel.
Police are conducting further investigation.