Reducing oil consumption using a lightweight drill

[Bob Culver]

It does make a very elementary task appear complex. it was common to turn a relief and drill drain holes below the loil ring. A releif below the compr ring not ideal as the leakage space is the gap times depth. A very slight chamfer on the top edges of oil rings, discontinued at the gap, another common practice. In the days when a wear step rapidly formed, not ideal with the top ring.