So I got tho motor completely apart today and all the main bearings look brand new, even the thrust shows little wear. All of the rod bearings on the other hand, are completely trashed. Im not sure how the oiling system works on these motors but shouldnt the Main bearins show significant wear if the rods do? keep in mind this motor had 207,944 miles on it when It blew up. Any ideas why there is little to no wear on the mains?

Also, I took the baffle out of the oil pan and found a broken rod bolt, I think it spun a bearing and that is what caused it to go, would that be consistant?

 

Depends on how they were ground, on the high side of low side of tolerance, and if it was align bored straight. The rods may be out of round and may cause more wear, not to mention they are taking the brunt of the force on the explosion when the fuel ignites. I'm not sure on the oiling on these also, if they feed from front to back or whatever, but I would imagine they would oil the same. Do the rod journals look burnt up or is the copper just showing?

 

I'm 99% positive that this motor is as it left the factory, just 8 years and 208K later. The journals on the crank look fine other than the one that lost the rods, but all the rod bearings are showing copper.
I've never had an LS1 apart until now so I dont know how tight the tolerences are.

 

I'm sure that is perfectly normal after freakin 200+K miles man, that is ridiculous. Wish my piece of junk lasted that long, I lost #2 piston at 97k miles. My own fault... Turbo's aren't real forgiving when you're getting knock retard. Take some pics of all the bearings laid out in pairs. If one side of the bearing is showing copper, the other isn't, or looks like it's in the middle and not all the way around, that'll tell you... it was out of round and you'll see where it was loaded. No biggie, get it ground .010 on the rods, see if the mains are within tolerance and polish or grind .010, assuming it didn't fry the journal with the rod problem. That's great. 208k is a lot of miles man.

 

Well the block is trashed so its going to be all new, only thing being reused is the rear cover and fuels rail. just kinda curious because I have had BB fords and chevys apart and never seen a huge difference in wear like this.