The oil line runs from the oil pressure relief valve through the dash and is secured to the back of the oil pressure gauge.
This is a 1/4 inch copper line:
- 2S4104 on all 8 cylinder engines up to serial # 1974 at length of 52 inches
- 2S4112 on all 6 cylinder engines up to serial # 3125 at length of 56 inches
Mid-year 1935 this copper line was abbreviated and a rubber flexible line A90483 was used from the oil pressure relief valve to a shorter copper line, which was secured to the oil pressure gage.
Same part for all 6 and 8 cylinder engines.
The copper line, long or short is secured to the oil gage input and/or the flex line with inverted flare tubing nut 12S703.
The reason for the change: the factory realized the copper line was flexing with movement while driving and oil pressure was lost.