curious has anyone done this? did you get any flakes in oil/coolant passages? is the risk of doing it this way worth it?

 

I would 100% not do that to an assembled engine. And if it's disassembled theres no reason to not have a machine shop do it.

 

It's like what, $20-$30 to have a shop resurface it?
How did you even afford an Evo?

 

No...

no.................

no.......................

no................................................ ...............

 

Yea I’m good my time is worth way more than what it would cost me to send it for proper machining. Plus good luck having a go at Fe vs the Al he was sanding on, assuming you are considering it on a 4G63 block

Not to mention all the microscopic Al bits in everything, some of them bits are going to be in that block 100%

 

I'm a machinist, and I have seen down and dirty decking like that. Although, I prefer blueing, and a stone, you can definately get a flat surface like that. Preferably, you would want it machined, but there is no shame in doing it like that. His setup was bad though. You should have the block on something solid and flat, not an old kitchen table. Lol. It also depends on how bad the warpage is. .002" can be done relatively easy, but .005" and up and you will need machining to guarantee flat. If that's the only way for you to do it, then go for it.

 

That looks like an aluminum block. Good luck trying to sand down an iron block. Lol
My guess is the edges will round and you will lift headgasket much easier with rounded edges.

 

Iron blocks can 100% be sanded, they're not that hard. Hell a crank gets polished using sand paper...

I have a 12x12x3 machinist block that I polish the deck with. Even after it's been surfaced by a machine shop. And then I do the final cleaning before assembly.

 

How smooth are you trying to get the deck to be? Is it because the machinist didn't get the surface finish right?

 

Iron can always be better than any decking machine will get it. It doesn't take a lot to get rid of all the machining marks.

 

The machine shop is the way to go and you know it will be done right. Also you will have a piece of mind that it was done correctly just in case any other problems arise.

 

Gotta love these forums. It never ceases to amaze me how people want to cut corners every chance they get in order to save a dollar only to spend a hundred to fix it later. Priceless.