This is taken from an OLD manual on car repair, so the dimensions mentioned are wrong, everything else is good to go
Fitting of Connecting Rod Bearings
The fitting of the connecting rod bearings is one of the most important repair operations that can be performed on a motor.
Misalignment produces knocks, causes vibration and excessive wear of cylinder walls.
Connecting rods come with the crank pin bearings finished to size so reaming is unnecessary and they only require a little sizing or hand fit ting for a perfect surface bearing-. This being accomplished by spreading a very thin coat of Prussian blue on the crankshaft to which rod is to be fitted.
Install the connecting rod on the crankshaft or arbor of the same diameter with the piston end hanging downward, as shown in Figure 26.
Draw the nuts tight so that the bearing is snug on the shaft. Swing the rod back and forth several times and then examine the bearing for blue spots.
The blue spots, or as they are termed high spots, indicate that the bearing and the crankshaft rub at these points only.
It is then necessary to remove the high spots on the bearing with a scraper, as shown in Fig. 25.
NOTE WELL, you do this AFTER you have determined with a micrometer that the crank PIN is perfectly round with the correct radius fillets etc... or after having the crank ground.
Repeat operation until all high spots are removed, and the bearing surface is smooth, and touches the crankshaft at all points.
The tension of the rod on the shaft should be snug enough so that when the piston and rod are moved to a horizontal position they will of their own weight move to a vertical position with a slight drag.
All burrs and other obstructions must be removed from the oil holes.
When the bearing has been fitted to the shaft, lubricate it thoroughly.
After the bearing has been properly fitted, the connecting rod must be tested for alignment, which can be done in the connecting rod aligning fixture, as shown in Fig. 27.
Fasten the piston pin in the upper end of the rod and slip the 1½" bushing in the lower bearing. Pass the plug through the holes in the Fixture and through the 1½" bushing.
Tightening Loose Main Bearings
To tighten the main bearings, care should be exercised in removing an equal number of metal shims from each side of the bearing cap.
The number and thickness of shims to be removed will depend upon how loose the bearings are.
If it is found there are no shims between the main bearing caps and the crankcase, the bearing cap should be removed, locked in a vise and with a mill file remove enough metal from the face of the bearing cap to allow the proper tension. (See Fig. 28.)
Considerable care should be exercised not to get the bearings too tight, as there is danger of scoring or burning them.
