I just picked up a 2005 6.0L LQ4 for my 71 C10. Got the engine on the stand and started to clean it up. WoW this thing has started to rust bad IMO. I would guess that I can flake off about .125" (maybe more) of exterior rust from the side of the block before I get to good metal. How much rust is too much, I deff dont want to loose any block strength from this? Its going to be boosted making some decent HP/TQ.

Any suggestions on how harmful this rusting can be to the strength of the block?

I can get better photos tomorrow but this is all ive got for now.

 

It's what's inside that counts. The outside, not so much. It's nothing to worry about unless it's attacking a seal point and a seal won't seal anymore.

I think it's fine, just sandblast it and repaint.

 

This is nothing compaired to what I saw. Minor surface rust which will easily wash of with a solution. Check the internal for rust.

 

Here are some more photos of the block. Just curious of your opinion if this has weakend the block at all?

 

not bad, Ive seen way worse, and they had 0 problems, just runner

 

This what mine looked like. Not an issue at all. Just clean it up and post some pics of the truck!

 

right on thanks for the input fellas. Got the block striped down last week...goin to get her cleaned up and paint the block this week

Heres a few photos of the truck. Im going for a nasty street/strip machine...stock bottom end 6.0L, turbo, Isky 218 cam, victor jr intake, with 4 spd muncie

 

Cool build. You should start a build thread on it.

 

sand plast it then decide if its ok or not

 

Ya, I would clean it up to get a better idea of the depth. It should be fine but it still needs striped down so it can be painted