Should I replace all my bearings?
Should I replace all my bearings? Hey guys so I just picked up an LY6 with 118k miles on it. I am going to do a cam swap and turbo it so I'll be pulling most of the motor apart. What I'm wondering is if I should go ahead and replace the main and rod bearings while I'm doing all this? I know that pulling the caps to examine the bearings will risk the health of whatever bearing is in there, so right now its a matter if should I trust the bearings or not. The motor had ~35psi idle pressure and when being revved the psi followed the rpm well. I will be replacing the cam bearings, lifters, pushrods, trunions, and valvesprings when I do the cam swap.
pull the cam and inspect the cam bearings. If they are fine leave them
pull a rod cap and see if they are fine. Replace with ARP bolts. Leave the alone if they look good.
No reason to waste money if everything is fine. Put that money towards a better turbo and LS9 head gaskets and either ARP head studs or the eBay specials that everyone uses.
pull a rod cap and see if they are fine. Replace with ARP bolts. Leave the alone if they look good.
No reason to waste money if everything is fine. Put that money towards a better turbo and LS9 head gaskets and either ARP head studs or the eBay specials that everyone uses.
Not going near ARP rod bolts, don't want to deform my rod ends. I ask mainly because a set of rod bearing is $20, cam bearings $30 (for the high end), and mains are $55. Pretty cheap to do, just didn't know if they would cause a nightmare breaking in with the old crank. I built my last motor with all the high end parts and it didn't impress me at all, lots of hype little to show for it. I'm trying to get a feel for what kind of miles people have on these motors before they see failures on the bearings.
I think it depends on 1) what you want your finished product to be and 2) your skill/experience level. $100 in bearings is a small investment given the scope of your build. (Cam, turbo, etc) If you're comfortable doing the bearings then do it- no need to roll the dice with whatever's in there. You don't know how the prior owner(s) treated or maintained the motor. However, if you're not comfortable doing the bearings or if you're doubting yourself a little, take a look at a couple of the bearings and just go with it. You may do more harm than good by tearing it down and rebuilding with new bearings.
The crank should be fine with new bearings. The crank will probably not have any real wear on it if the bearings are still good.
Looking at the cam bearings is hit or miss. Most LS cam bearings have considerable wear, however, I've seen motors come apart with rough cam bearings and good rod/main bearings. To get the full story you'll have to look at the rod and main bearings.
As for miles before failure, I can't help you there, but I bet there are a lot of factors at play (maintenance, how the engine was run, how the engine was run or pulled at the salvage yard, etc) that decide how long the bearings last.
The crank should be fine with new bearings. The crank will probably not have any real wear on it if the bearings are still good.
Looking at the cam bearings is hit or miss. Most LS cam bearings have considerable wear, however, I've seen motors come apart with rough cam bearings and good rod/main bearings. To get the full story you'll have to look at the rod and main bearings.
As for miles before failure, I can't help you there, but I bet there are a lot of factors at play (maintenance, how the engine was run, how the engine was run or pulled at the salvage yard, etc) that decide how long the bearings last.
