Performed a heating pm on an oil boiler. Brushed and vacuumed. Replaced the oil filter, nozzle and strainer. Started and checked the safeties. Performed a combustion test. 8.2% o2, 35 ppm, 84.0% efficient System is operating properly. The oil line was plugged and very little oil coming out at the burner. Blew out oil line and bled the line. There are a few drops of oil on the bottom of the oil tank, but unsure if there is a leak or from when they delivered oil. There is streaks going down the side at the fill pipe. The tank is full. The pressure/ temp gauge is reading higher pressure than what is in the boiler. The pressure relief valve is not dripping.