I've read this forum so much it made me nervous so I thought I'd take a look at my rods. There seems to be a knock at higher speed, around 30-35. It doesn't do it if you just rev it up sitting still. The rods slide back and forth quite a bit it seems. I put a piece of newspaper in and the crank still moves but the rod didn't seem loose but maybe it could be a little tighter. Maybe it could be twisted? Maybe I should have not worried about it. Here are pics of rod number 2. Any thoughts?
Number one rod doesn't look like that. It has barely any wear. Oil grooves look straight.
All the other rods look good. I bet that one is twisted. I took a shim out, the others are ok with no sign of irregular wear.
Corey, if the rods slide back and forth on the cranking easily, they are too loose. They should be so that it takes the light tap of a small hammer to move them back and forth.
That should settle down the noise you get at fast cruise.
And, yes, they rod could be twisted.But,try this. If it were mine, I would take a bearing scraper and knock down the high spots. Then 'adjust'.Also, that should be crank pin, not cranking.
I got it back together. It did sometimes make some funny noise idling intermittently but it doesn't seem to now. Was kinda hard to crank guess I need to let it run at idle a bit before I go driving so it can loosen up. I bet there is a problem with that rod because all the others looked fine.
Corey, a sprung rod also causes piston slap and pin noise. Sounds to me like a good average fun car engine. Drive it and enjoy it.
Looks to me like a case of really soft babbitt. This is indicated by how the bearing metal has wiped across the oil grooves and the grey color of the bearing.