Bypass Valve at Start Up When the engine is not running, the valve (plunger) closes the passage to the lubricating points. As soon as the engine begins to run, the oil pump sucks oil from the oil sump in the crankcase and forces it to the bypass valve. The bypass valve is then forced down, under the pressure of the oil, and opens the oil gallery to the lubricating points by bypassing the oil cooler. |
