What is the maximum oil pressure allowable for ground start?

• A. 150 PSI
• B. 182 PSI
• C. 200 PSI
• D. 210 PSI

Answer: (B)

Oil pressure during a ground start is limited to a value that protects the engine’s lubrication system. The lubrication system uses a relief valve that opens to keep pressure from rising too high, especially when the engine is starting and there’s minimal oil flow demand. For this airplane, that relief setting is 182 psi, so the maximum allowable oil pressure during ground start is 182 psi. You’ll see pressure rise toward that level as the system pressurizes, but readings above it indicate an overpressure condition that could damage components and would require stopping the start or investigating the relief valve or oil passages. The other numbers are not the defined maximum: one is below the limit, and the others exceed the designed relief setting and aren’t permitted as the allowable maximum during a ground start.