Thread: Rod bolt installation

Tweet

Built a 454 using original truck connecting rods. Used ARP rod bolts #135-6002 and did the torque down on the bolts 3 times as instructed. Later, after the engine was installed in the car i became aware of the fact that the machinist did not chamfer the holes in the connecting rods before pressing the bolts into the rods. Engine has been running great for several rod runs with some heavy duty use, about 500 H.P. and turning upwards of 5500 r.p.m. Just wondering if the rods had enough chamfer or any at all, or if I need to concerned with this at all. So far, the engine has performed great. New to the site but look forward to much engine talk. So hello and thanks for any insight into my question.

well if the bolt head was flat to the rod your ok .or are you talking a bout the cap were they say you should spot face them for the flange nuts ? i do the chamfer the rod and cap before i cut them and work the parting lines cap and rod with a file and work any burs off the big end of the rod if your talking about the top of the rod were the head of the bolt go s thru ?

aaThanks for the reply. The part of the rod I was referring to is the main body of the rod. I have been made aware that ARP bolts have a radius under the bolt head that may require a small amount to be chamfered into the top of the bolt hole in the main body of the rod. My concern is that my rod bolts may not have seated completely if my rods did not have the chamfer to match the radius under the bolt head, and in time due to the stresses in a running engine ,could sink a small amount further into the rod and cause the torque value to decrease to the point of bad results! Car is a tube chassis, so pan removal is quick and easy, I may drop the pan and check the torque on the bolts and be done with it.

Originally Posted by Walker Power

Thanks for the reply. The part of the rod I was referring to is the main body of the rod. I have been made aware that ARP bolts have a radius under the bolt head that may require a small amount to be chamfered into the top of the bolt hole in the main body of the rod. My concern is that my rod bolts may not have seated completely if my rods did not have the chamfer to match the radius under the bolt head, and in time due to the stresses in a running engine ,could sink a small amount further into the rod and cause the torque value to decrease to the point of bad results!

well that part has some chamfer. from gm they just bore the hole abit bigger .you want to make sure were the flat is cut on the bolt head will not hit the rod side were the beam is. the head looks like a ..D .. the flat spot can hit as well i look over all this stuff then i recon the rods if the head is flat to the rod your are pulling on the head . if not flat then you would be working on the chamfer.not good. i chamfer and spot face where the flange nuts seat as well. the part your worry about. i have not seen any bolts getting hang up there. but i look them over good before and after i press the new bolts in .the guy should of check all this ? if some thing did not look right he should of fixed it .or you would of seen it when going together ? it is hard to say if any things is wrong with you rods if you are worry you know what to do.i think you would of seen the heads hanging up

Thanks again for taking time to respond. I am new to this site and computers and am still learning how to get around this forum and finding out all it has to offer. So far, it looks like a gold mine of information and a lot of fun. Did not know about this site before just a week ago, found it by chance, but will visit often. The study of the internal combustion engine has fascinated me since i was a kid, so this site is big time entertainment for me.