Over-Torqued Rod Bolt
 

In assembling my crank I followed Wayne's method of 15lbs/foot + 90 degrees. All worked out fine except my first bolt/nut. I ended up going slightly over the 90 +/- 2 degree.

Not feeling comfortable with that I picked up 2 more bolts and nuts for that rod. Question I have is, should I remove BOTH bolts and nuts for that rod or can I just replace the one I overtorqued?

HI you already have doubt in your mind about the bolts, so change both bolts, which is why you got 2.

regards mike

Did you measure the torque as you hit 90 degrees? My Bruce Anderson book gives a range of values for this torque. I've found that as you approach the high end of the range the nut turns much less per added pound which I interpret to mean I've reached the correct torque. I think the best method is to measure the stretch but if you don't do that I'd like to at least know what the final torque is. I guess the 90 degree think is to get an approximate stretch. Is there a range of allowable stretch?

My personal opinion is that people tend to undertorque these bolts. The ones I've used a stretch guage on took quite abit more torque than specified to reach the stretch number.

-Andy

Where do you normally find these stretch values?

The stretch value should be included with the rod bolts. Every bolt package I've opened from ARP or Pioneer has a little spec sheet with the bolt stretch included.