I'm into a D2 5U engine which has an abundance of things wrong with it. I gauged the crankshaft throws, found about 0.002 flat, about 0.008 clearance (blue plastigauge). The throws are worn 0.002-0.003 except in the middle where the oil clearance is, so there is a high middle area between two worn areas. In addition, there is rust pitting on two of the throws but it in this middle area where the bearings don't run. Acording to the shop book this crank is usable, is well short of the maximum allowable wear.
Can I rely on the judgment in the book? Or is this crank barely marginal? Or can I expect a reasonably long life from this engine just bolted back together? A car engine with a crank like that wouldn't make it out the driveway.
Please put forward some experience on this if you will. Old magnet? SJ? Anybody else? Thanks in advance,