internally balanced 360 crank (BIG PROBLEM) need input
Throw that crankshaft in the trash.
Unless he is willing to pay someone else to have that cast crank magnaflux checked for cracks at his expense and give you a receipt from their shop with contact info, that crank is garbage.
A balancing shop may be able to correct that crank, but after it bounced hard enough to crack a main cap, I wouldn't trust it as far as I could throw it without checking it.
If it were my engine, I'd check the main bearing saddles for cracks too and possibly just have the block torn down to have it magnaflux checked after something like that happened.
The bearings are garbage now, too. When that weight came off, that crank was no longer balanced, even if it ever was and that takes a toll on bearings and journals.
As previously posted, you go into the side of the counterweight with moly, like this-
Take him up on his warranty. End of debate. I know he wants to fix the engine and I'm willing to bet that most of the work done was probably pretty sound, with the exception of the crank.
The only exception to doing that, in my opinion, would be to tell him that the crank needs to be balanced by an experienced balancer, using the method shown above and that the block is magnafluxed by another shop, to check it for damage, as well as the crank, if it is intended for reusing.
Anything else on the lower end of the engine that could potentially be reused should be checked.
A friend of mine rearended someone in a left turn lane that stomped the brakes, after oncoming traffic ran a red light. The shock to the car caused the timing chain to jump a tooth. Fortunately for him, it wasn't enough to hurt anything else, other than the timing set and made it run awful, but the point is; shock can do unseen things to engines. For all you know, you could have invisible cracks in ring lands or in a connecting rod, connecting rod bolt or anything else down there that may last several thousand miles and fail, without inspecting.
You wouldn't throw a transmission in reverse at 40 and expect it to be ok, without inspecting it. All of those parts in that engine were hammered hard. The timing chain could have also been stretched.
Tear it apart, check everything for cracks and don't run any risks, regardless of who you decide builds the engine.
Throw that crankshaft in the trash.
Unless he is willing to pay someone else to have that cast crank magnaflux checked for cracks at his expense and give you a receipt from their shop with contact info, that crank is garbage.
A balancing shop may be able to correct that crank, but after it bounced hard enough to crack a main cap, I wouldn't trust it as far as I could throw it without checking it.
If it were my engine, I'd check the main bearing saddles for cracks too and possibly just have the block torn down to have it magnaflux checked after something like that happened.
The bearings are garbage now, too. When that weight came off, that crank was no longer balanced, even if it ever was and that takes a toll on bearings and journals.
As previously posted, you go into the side of the counterweight with moly, like this-
Take him up on his warranty. End of debate. I know he wants to fix the engine and I'm willing to bet that most of the work done was probably pretty sound, with the exception of the crank.
The only exception to doing that, in my opinion, would be to tell him that the crank needs to be balanced by an experienced balancer, using the method shown above and that the block is magnafluxed by another shop, to check it for damage, as well as the crank, if it is intended for reusing.
Anything else on the lower end of the engine that could potentially be reused should be checked.
A friend of mine rearended someone in a left turn lane that stomped the brakes, after oncoming traffic ran a red light. The shock to the car caused the timing chain to jump a tooth. Fortunately for him, it wasn't enough to hurt anything else, other than the timing set and made it run awful, but the point is; shock can do unseen things to engines. For all you know, you could have invisible cracks in ring lands or in a connecting rod, connecting rod bolt or anything else down there that may last several thousand miles and fail, without inspecting.
You wouldn't throw a transmission in reverse at 40 and expect it to be ok, without inspecting it. All of those parts in that engine were hammered hard. The timing chain could have also been stretched.
Tear it apart, check everything for cracks and don't run any risks, regardless of who you decide builds the engine.