Next job, check the oil flow to the valve train. The oil distribution valve is fed by a tiny 3/16-inch line, making any blockage a major problem. Cranking the starter shows oil running through the line, but it retreats the second the engine stops turning over - possibly indicating a bad check valve. Turns out, there is no check valve in the system, so I clean everything up and make a check valve similar to those on Harley-Davidson motorcycles.