Most of the thick oil at startup actually goes through the bypass valve back to the engine oil sump and not into your engine oil ways.

大多半厚(粘稠)的机油在启动时实际上通过旁支泄压阀又流回到油底壳而不能进入策动机油道。

youdao

United mechanics who inspected the engine found that two shop towels had been used to cover openings in the oil sump area, instead of protective caps.

CNN: US Airways, United face FAA fines for safety violations