I removed the main bearing caps and checked the main bearing bolts to be sure they have not strecthed. I blow air through all of the oil passages to be sure they are not plugged up. Sometimes you will find one plugged up with crud, especially, if you a major engine failure with chewed up bearings. This was not the case with this engine. The other thing that plugs up passage ways in block and other things is a Dirt Dauber. They can ruin an engine overhaul. Each time I stop on the engine I will cover everything up. This keeps dust out and most of the Dirt Dauber out. Each time I start on the engine the first thing I look for is traces of Dirt Daubers. They will leave the hole plugged with a white plug. You have to clean them out and clean all of the dirt out of the hole.
The first picture shows the main bearings in the block. I put all the bearings in and put the matching bearing in the cap. These are matched sets to keep the oil clearance right.
The crankshaft also went to the machine shop to be turned and came back with the rods polished standards and the mains were turned to .010 undersized. I put the crank in the block and used Plasti Gage to check the oil clearance. If you have to much or to little clearance the engine will not live. The clearance is .0017 to .0047 mine measured .0027 to .0030 . I removed the crankshaft and greased up the bearings and reinstalled the crankshaft in the block. I use a white Lithium grease to coat the bearings. This gives them so lubrication while the engine is turning and building oil pressure. It will also stay in the engine if the engine sets for 5 or 6 months before being cranked.
I installed the main bearing caps and snugged them up as even as I could before torquing the caps. The main caps torque to 150 ft lbs. I torque the caps in 3 steps, 100, 125 & 150. I torque each cap and then turn the crankshaft to see how it feels. This is to make sure it is not binding the crankshaft as I tighten the crankshaft. If everything is right The crankshaft will turn as easy at 150 ft lbs as it does at 100 ft lbs of torque. And this one was right!!
The next step is putting in the pistons.
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