Cast iron heads, surface rust

[Bill Chase]

Any of you had decent results using a light solution of clr for rust removal on heads and blocks.

[lance flake]

I put a rusty block in a container with very minimal amount of clr mixed with water and it came out better than I expected. Doesn't compare to thermal clean and shot blast but it was useable.

[CGT]

Any of you had decent results using a light solution of clr for rust removal on heads and blocks.

I use CLR for a lot of stuff like that. Works good while not being too crazy strong. Makes aluminum blocks and heads look much nicer also....usually. It can make freshly machined surfaces look a little funky if left on too long before rinsing or if in direct sun.

[BOOT]

I was gonna say it has phosphoric acid which is a rust converter but after a quick google looks like maybe not anymore https://en.wikipedia.org/wiki/Calcium_Lime_Rust

[rebelyell]

NAPA's Aluminum Brightener has a big dose of Phosphoric Acid.
Other brands similar

[CGT]

NAPA's Aluminum Brightener has a big dose of Phosphoric Acid.
Other brands similar

That's my next go-to after the CLR....but requires more caution than the CLR. I have had real good luck with it.

[Bill Chase]

I put a rusty block in a container with very minimal amount of clr mixed with water and it came out better than I expected. Doesn't compare to thermal clean and shot blast but it was useable.

I just want to clean these heads up enough to mag and pressure test, if they pass that I will have them hot tanked.

[rebelyell]

I put a rusty block in a container with very minimal amount of clr mixed with water and it came out better than I expected. Doesn't compare to thermal clean and shot blast but it was useable.

I just want to clean these heads up enough to mag and pressure test, if they pass that I will have them hot tanked.

some DIY carwash pressure washers will let ya do greasy stuff; not all