if a crank doesnt need to be turned down and your just gonna put new bearings on it is there any special way to prepare it?? my crank play measured .002 of play. so i assume just bearings would be fine but i need to be sure.

 

You shouldn't need to do anything too special..I assume you mean you had .002 of endplay. This is a little tight.. .005 is better, but at least you've got some!! As long as there is no burrs or bearing material on the bearing surface, you should be ok!

 

i always polish it, clean it, run brush through the oil feed holes, measure all the journals and pins and record the measurements

 

Polishing involves mild abrasive paper, such as crocus cloth or flint paper. Aluminum oxide abrasive is very hard, and can stick into the surface of the metal, creating accelerated wear on your new bearings. Softer abrasives are better, adn the crank should be thoroughly washed and dried after polishing.

You should also pay a little attention to the thrust surfaces on #5.

Ede's suggestion of using hose brushes or rifle bore cleaning brushes to clean oil passages is worth following. .25 caliber brushes are a good size for the oil galleries in stock cranks. Treat teh journals to a rust preventive coating right after washing and drying, Avoid touching the polished surfaces with your bare hands (nitrile gloves are great for this, as well as bearing installation).

Before the final polish and cleanup, you might also want to chase the threads in the crank snout with a 7/16-20 bottoming tap. Keep the same tap in the handle, and clean out the six holes in teh rear flange, then clean out the pilot hole in the rear of the crank. Make sure the keyways milled in the crank snout are free from burrs and contamination (toothbrush), clean up any rust and burrs from the snout itself.