Replacement block cracked?

A few years ago I had a new short block installed in my 2021 4Runner after a piston rod broke. My fault, would rather not get into it here. Recently the shaft on the harmonic balancer broke and damage was done to the crank snout, key way, timing gear, and balancer. There doesn't appear to be any other damage. The bearings, and cylinder bores all look okay. I went back to the shop that originally replaced the block and they are willing to fix it under warranty by replacing the crank, the bearings, and the timing gear. They sent some pictures and I noticed what looks to be a crack at the base of a bolt boss. I have encircled the area in the picture. Is this something I should be concerned with? As you can see this would have been in the same area as the other damage. Could this have been caused by the balancer breaking? Or the balancer having been improperly installed? I initially took it to another shop, closer to home, because I thought it was just an oil leak. He mentioned that the way the balancer broke and the damage done to the key way indicated, to him, that excessive force was used to install the balancer.

 

Just about every

$30 2010-2024 SDPVorn Armrest Cover for Toyota 4Runner Center Console Pad with Organizer Storage Pockets, Black Faux Leather Arm Rest Lid Protector Cushion Interior Accessories (2010-2024)

2010-2024 4Runner engine looks exactly like that. Not cracks, casting marks.

Edit: many, not necessarily "just about every"...

 

Thank you.

 

The casting marks from die wear are common on later-year 5th gens (like 2018+) on the timing cover. How many timing covers have you pulled to see this area on the block?

 

None. But every time this question comes up, whether on the timing cover or elsewhere, the same answer is given.

https://www.4runners.com/threads/cracked-appearance-on-front-of-new-engine.37083/

https://www.4runners.com/threads/is-this-cracking-normal.41683/

For a few examples. I wouldn't bet the farm that the OP's is the same, but chances are it is.

 

These are not the same as the picture I posted. The "crack" in the picture I posted is obviously the block behind the timing chain cover. Here is a closeup.

 

I will bow out of this thread. Good luck with your investigation.

 

Since this block is disassembled and not currently installed, if you really want to know if this is a real crack versus a casting mark, you will have to get either a dye penetrant test, or better yet an eddy current test performed.

 

Every single one of these you posted is the timing cover.

 

I requested the shop to perform a dye test. He replied that he had noticed these marks and they are casting marks. He used the fingernail test and found them to be ridges. He also sent me more pictures of similar looking marks from various places on the motor that look similar and they are all casting marks.

Thank you, everyone, for your input.

 

FWIW, in the casting industry those marks/ridges are known as "heat check".

I worked as an engineer in that industry for a while.