On all taxes (except on motor vehicles) which are hereby levied and which are not paid before January 16, there shall be added an additional penalty of three percent; and on all taxes not paid before February 2, there shall be added an additional penalty of seven percent; and on all taxes not paid before March 17 of the following levy year, there shall be added an additional penalty of five percent; and the Greenville County Tax Collector shall issue his execution therefor and for penalties due, against the property of the defaulting taxpayer, according to law. (Prior code § 1-5-35)