Oil

[beige_alert]

Our HP (nowadays “Agilent”) model 1090 HPLC (High Pressure/Performance/Price Liquid Chromatograph) had another one of its bad days. First it looked like the detector or maybe its UV lamp was broken, then it looked more like the pump. I changed the hydraulic oil in the high-pressure pump and bled the hydraulic lines, and once that started working right the detector gradually settled down and started looking better, so I suppose it was just air/whatever in the detector flow cell. I hope. The instructions for changing the oil don’t have a “step 47: get oil all over everything and make a big mess” line, but they ought to.