1963 GMC Carryall V6, doing a carb O/H in a rest area along side I-40 back in 1973. After everything was back together I noticed one mounting nut missing. Found another in my toolbox and we were on the road again, I thought. As soon as I fired up the engine it sounded like a rod was trying to beat its way out the side of the block. 90 miles away from home and dirt poor we had no choice but to move on. Drove the final 20 miles to our destination (big dune buggy meet) with the hard clacking driving me nuts. After the meet was over we headed the 110 miles back home pulling the buggy on the trailer. About 40 miles from home the noise went away. No noticeable difference in how the truck ran. It bugged me so much that I pulled both heads finding the missing nut melted into the top of #4 piston. Put it all back together (left the nut where it was) and put another 20000 miles on without any troubles.ðŸ›
