1. Cleaning your block is extremely important. After the block is machined, the machinist will throw the block into their “dishwasher” to clean off all honing oil, shavings, and so on. It’s also a good idea to rewash your block when you get ready to assemble. Scrub it with hot, soapy water and use bore brushes on all lifter bores, oil passages, and so on. Any stray piece of dirt/metal can find its way into the oil pump and be pumped into the bearing surfaces. You can also use an air hose to clean out the smaller areas such as the main and cam bearing oil feeds.