Chemicals to Clean Water Passages in a Block

[Guest rsd9699]

What kind of chemicals would you use to clean the rust and scale from the water passages of an engine that has sat for a number of years?

Something like concrete cleaner that has a lot of phosphoric acid or the old number 7 from DuPont?

Thanks

Ron

[Guest JR Cars]

I have no connection to these people, but have had super results! I buy the concentrated jugs, then mix it myself. Pour in in the block, and just let it sit for a few days or even a week or two, depending on the severity. For great rust removal Safest Rust Remover

[Guest martylum]

Hi-Several years ago i disassembled a 36 Lincoln K V-12 engine stored for many years without antifreeze and found the cast iron jugs to be completely filled with powdery rust upon removal of the core plugs. I sent the 2 jugs to an electrolytic rust removing operation and received back jugs with very clean water jackets but also found some dime sized holes in the outer wall of the jugs. Fortunately, a sonic test of wall thickness of the cylinder walls and valve areas showed adequate thickness for a rebuild so I had the holes welded up and the engine rebuilt.

Point is you don't want to use anything too agressive or you may ruin the block. If it's an easy to replace block, then no problem. I'm going to deal with this same problem again in a 53 Buick V-8 and will probably take the least aggressive approach as this engine comes out of a 53 Skylark.

Machining an engine block during a rebuild is expensive enough you don't want to invest unless you have enough meat in the block in critical areas.

Marty Lum

[Guest rsd9699]

I have scanned the net for simple solutions to simple problems. In this case, rust removal. Everyone says stay away from sulfuric and hydrochloric acids due to porous nature of cast materials or iron in this instance. I can see that part.

But phosphoric acid only works on the rust and not the iron in the block. It seems to work okay in the navy jam stuff (no free plugs - ha ha). It looks like to me that it would work in cast iron unless it works on the stuff mixed into the cast that would make it porous. Any chemists out there?

The "other stuff" in the link provided does not provide a msdn list so I am not sure of what they are hiding.

Thanks

Ron

"May the breeze be with you!"

[Guest Backyardmechanic]

go to Evapo Rust :: Harris International Labs You can buy it from auto zone,pep boys, tractor supply, Harbor freoght tool and many others.

Vern

[92GTA]

Can I run straight Evaop-Rust through my cooling system then flush?

EDIT: I found out I can: http://www.evaporust.com/evaporustcsc.html

Edited January 7, 2011 by 92GTA (see edit history)