Following a full engine reconditioning, the engine oil was not circulating, and no oil was reaching the top of the engine. The customer queried whether the oil pump on this engine required priming.

The engine had been rebuilt due to a blown head gasket. Upon reassembly and first start, no oil was present at the filter or in the valve train. The oil pump was reused during the rebuild. Initial attempts to prime the oil system by filling the filter with oil and injecting oil through the oil pressure switch port were unsuccessful, and oil pressure was not established.