I'm dropping in a used motor i bought, I've gone through the top end and everything is fine but i wanted to check the bearings in the bottom end. Can i unbolt the main and rod caps to check the bearings and torque everything back down with no ill effects

 

Can you? yes. Should you? Maybe. Do you have any reason to suspect a problem? If you're gonna do it, get some assembly lube for the bearings before putting the caps back on, get a good torque wrench, verify the calibration, use 30W oil on the threads, the rod bolt nuts go to 45 foot pounds, the main bolts go to 70 foot pounds.

 

I just dont want to put it in and then find a problem with it. But visually everything looks fine and tolerances are good. and yes i would reassemble everything the correct way.