I replaced the crank shaft in my 1999 F150, 5.4 because of a spun bearing.
The full story is on my other posts here and in the 97 forum.
After torqueing everything down the engine turned very hard. I pulled the oil pan off to see what was going on. I loosened each rod cap a little to see which one was sticking. The second rod back from the front of the engine was binding up somehow. As soon as I loosened it the engine freed up, so I pulled the cap off. Here are pictures of what I found. The bearing on the side is showing uneven rubbing. I checked carefully and found no dirt or debris under the rod cap that could have caused it to bind. Plastiguage showed .002 clearance, within tolerance according to the book.
I am wondering if I have a bent connecting rod? Maybe bent causing it to ride at an angle on the crank?
It is over a 120 mile drive to the nearest machine shop, so I won't be able to get anything checked for at least a week.
I am going to pull the head on that side and pull that piston out to see what it looks like.
Any other ideas of what is going on here? The rods that were chewed up were on both rods just behind this set. The bearings had not completely spun out, I got things shut down on time but they were chewed up pretty bad.
Damaged was caused by low oil volume. The timing chain guide broke, timing chain rubbed the chain cover causing the oil pickup screen to clog with metal filings. It was still pumping oil, but not enough when I was pulling weight working it hard.
The journal checks out good. It is a rebuilt crank, and checks out good. Not out of round or tapered. The bearings pictured are brand new. I put them in and turned the engine a dozen or so times. The wear marks on the bearings are from turning it.