Connecting rod bolts

[Subfixer]

I've got a light knock that I hear around 2000 -2500 rpm that's driving me nuts. Above that rpm, there's too much other noise for my 1/2 deaf ears to hear it.


Not sure what it is, but I want to pull the rod caps and check the bearings. The last owner lost an oil cooler hose, but I don't know how far the car was driven after the hose let go.


Anyway, since the rod bolt torque is so many ft/lbs plus 1/4 turn (or something like that), I'm wondering if the stretched bolts are one time use and should be replaced.


Thanks in advance...