The Stovebolt Site Forums The Shop Area Engine Shop 216 Connecting Rods 1950 3600

I had a little extra time this weekend so I figured I'd get the rods ready to send in for conversion to insert bearings. I didn't have my manual with me (I'm working in my Dad's shop)so I figured I can't mess too much up by just taking the pistons off of the rods. So, I clamped the rod in the vise the long way so I could grip it as close to where the clamp bolt is as possible and proceded to remove the bolts, wrist pins, etc.

When I got home, I noticed in my manual the fancy holding device for holding the piston/rod assembly when tightening the clamp bolt and the warning to the effect of "Do not clamp the rod in a bench vise or you run the risk of twisting the rod." They also show a fancy device for checking if a rod's bent or twisted.

I highly doubt any of this equipment is still around so what's a hobbyist supposed to do when loosening/tightening the clamp bolts on the rods? Is it likely I tweaked my rods in the process and I shouldn't use them or do they check and correct any possible twists when they machine them for the inserts? If the shop makes sure they're true, then how do you hold them when you tighten the clamp bolt when attaching the pistons and pins? I also didn't see a torque spec for the clamp bolt in my manual. Does anyone know what that should be? Thanks, Shawn

They should check them when converting them, if not have it done.
I clamp a large punch, that fits the ID of the wrist pin, in my vice while doing this job and slide the assembly over the punch while tightening or loosening.

Thanks for the tip Dave. Does anyone know the torque spec for the clamp bolt on the rod? Unless I missed it, the only spec I saw in the manual was for the rod caps.

I have never seen it in any manual but I torque them to 30 Ft Lbs

Thanks again Dave. I appreciate it. Shawn

Clamping a rod lengthwise will keep it from twisting, as long as the vise jaws don't put nicks in the beam section. I use soft copper jaws on anything that might be damaged by the serrations on the hard steel jaws. The precaution is about clamping a rod near the big end, and putting a lot of torque on the bolt at the top. That puts a twist into the beam because stoveblot rods are pretty flimsy where a twist is concerned. Twisted rods create an oddball angular wear pattern on the piston skirt, and a really strange-sounding knock!
Jerry

Yes, I forgot to mention I was using brass inserts on the vise when I clamped the rods in there. I was able to grip the entire length of the beam so that makes me feel better. Thanks Jerry. Shawn