What do Oil Wells do?
Oil Wells are where Oil is produced. Upgrade them to increase Oil production and storage.
To add the Fuel from the Oil Wells to your resources, simply click each Oil Well. You'll see the Oil move to your resource counter and your resources will increase. Fuel produced by your Oil Wells cannot be used until clicked in this way.
Once the Oil Well Storage capacity in an Oil Well is reached, that Oil Well will not produce any additional Fuel until you click it and release the resources. Make sure to check your Oil Wells frequently and click them before they fill up so that you don't lose valuable resources!
Oil Well Income can be increased by using Oil Well Boosts or by using diamonds.