What is this?

This is not a tacoma, but a toyota

 

The surface imperfections? Normal for the casting process.

 

Alright just wanted to be sure

 

No problem.

 

Character.

 

Actually, how does this happen? Do i have anything to worry about? Ive just never seen this

 

Any help or just info would be appreciated

 

I'm not a metallurgist, so this is gonna be my amateur guess. It is from the liquid metal flowing and splashing into the die and starting to cool unevenly. As more volume fills the die, the whole thing can then cool at a more or less constant rate. It is just a surface thing as casting itself is a very technical process for parts like engine blocks. Flanges, thickness changes, and feature areas are all designed and modeled to ensure flaws are minimal. Sorta why we can have comparatively light engines with high output and long life. Blown head gaskets are a fraction of what they were just 25yrs ago.

 

I appreciate it, im just trying to understand it. Looks abnormal but im really hoping its not anything serious

 

The stuff that would worry folks would be seeing large voids from air bubbles. Porosity and warpage are the big killers for castings.

 

So would you say the block is fine?

 

100%.

I would bet that you could fine that same surface on some cast AL parts on your Taco. I know my transmission has that appearance.

 

Appreciate the info man i know nothing about engine blocks

 

You're welcome!

Totally understandable.