Back in '84, I began restoring my '64 Galaxie. It orginally was my dad's and I bought it off him in '70. It had fallend into disrepair and had sat out behind my house for about 10 years when I began restoring.

Being a bit on the lazy side, I got tired of sandblasting very soon into the job and began looking for alternatives to clean rusty parts. I soon discovered soaking in diluted HCl (muriatic acid), the rust would be dissolved and leave the metal gray in color.

I partly filled a plastic trash can full of this brew and soaked, backing plated, brake drums, battery trays, brackets, exhaust manifolds, heads and anything that was all steel or cast iron. If any aluminum or brass is present, the part will fizz until dissolved. Otherwise, I could leave parts in the soaking brew for weeks and the cleaning would stop at the steel or iron.

Being bare metal, I could see it turn orange as I rinsed off the acid, but working fast to get it protected helped that problem.

I found a GT 390 engine in a junk yard and bought it for $10. It had sat outide for many years. I discovered it had a rod through the block, but after soaking the rusty intake, heads, and exhaust manifolds, I was able to get a premium price at the swap meet
for those cleaned parts. - -

I, also, restore tractors and the fellas in the tractor circles are using electrolysis. They use a battery charger with a mixture of washng soda. That does a very nice job too, but the activity is mostly "line of sight". Nooks and crannies are missed.

Ken McWilliams
Dayton, OH
kenora1(at)aol(dot)com - - - -

 

How much do you dilute the muratic acid?

 

I agree that muratic acid can, and will do a great job on rust. (and paint for that matter)

However it has been my experience that you can lose too much of the metal in the process. Specifically casting numbers, and casting marks seem to get hit pretty hard by it. Additionally it seems to leave larger "pock" marks. My number one problem with it, is that you can never get it all out, between the seams, and it shows up later as a white powdery line around seams....long after you have painted. Of course, on a straight piece of metal this would not be a concern.


Electrolysis as you mentioned also has limitations, and so does sandblasting, and any other method of rust removal. Different parts will do better with different methods. I think you should try them all, and see what works best for you.

This is a good post, and many people will be helped by it. I just wanted to point out that its not a cure all.

 

Drew,

I agree with you about trying to clean assemblies. Where there is an opportunity for the acid solution to wick in by capillary, there will be seepage later. This can be overcome in a pressure vessel and running through a few cycles of vacuum and pressure - but not a typical garage piece of equipment.

As far as etching too far. I've not made the same observations. I've left parts in the tub for weeks. If the surface is badly pitted, the pits will be cleaned out, but the pits remain.

The jobs that I've gotten have been similar to "hot tanking" (which is a hot solution of sodium hydroxide in water). I do have to deal with the free chlorine released from the hydrochloric acid, which doesn't happen when "hot tanking" and is generally a more acceptable procedure for machine shop operations.

Yes, it nicely removes the paint, also.
Single parts without overlaps is by far the best type of object to soak.

As far as dilution to another question. About 10% acid in the water is sufficient.

CAUTION!!! CAUTION!! CAUTION!!

Always pour acid into water -- not water into acid. Water reacts violently when poured into acid and it will be thrown back into your face!!

Ken McWilliams
Dayton, OH
KENORA1(at)AOL(dot)COM

 

I have a concauction for you guys, and I am being serious, but before I tell you what it is I will tell what it did. I had a pair of Chevy double hump 327 heads, with pretty bad surface rust all over, in the ports and everything. I dipped it in the solution for about 2 weeks they came out rust free, power washed em made sure I got the solution off.

1 part molassas to 3 parts water

I have heard of mixes as weak as 1:20 but I think a mixture of one part molasses to three parts water is good.

All you have to do is find a container large enough to fit your parts and the molasses and water.

try it, just be warned about the smell, it get pretty bad.

Acid is a bit to strong for me. oh and this is environment safe.

 

Speaking of the environment, how exactly does one dispose of a 40 gallon garbage can full of grungy mriatic acid solution without contaminating anything?

Batman

 

i take my antifreeze and oil and dump them around my garage to keep the weeds down.
dont know what an acid would do.
but you can maybe dump it alittle at a time.
i dont ever remeber dumping acid though.
the strongest acid ive messed with is battery acid and it was on the inside of my garage and in my driveway.
maybe you can come up with a way that could help others.
like disolve a driveway or something.
hope you can get rid of it.

swanny

 

[updated:LAST EDITED ON 14-Dec-02 AT 02:24 PM (EST)]I figure that my college classes might be of assistance here. In my geology classes we use a lot of muratic acid (undiluted) to clean crystal specimens (plus we do get bored and just like to watch carbonate rocks fizz during exam week.. hey its cheap college entertainment ).. With the acid we have left over we simply neutralize it with household baking soda... just keep adding it to the acid until it stops fizzing.. this forms carbon dioxide gas and a harmless salt (NaCl aka table salt). Once its neutralized, we simply pour it down the drain.

With a tub of acid, I think it might take several boxes of baking soda, but it would be the safest way to take care of it, but I can't guarantee that whatever oils or crud that was on the parts will be taken care of, but the acid will be.

Whooo hoo, finally a question I can answer, guess all my chemistry classes paid off for something

Jon

 

>Whooo hoo, finally a question I can answer, guess all my
>chemistry classes paid off for something

And I'm willing to bet, Jon, that you've been whining to your parents/friends all along about how you're never, ever going to use any of the "stuff" they're teaching you at school.

 

<i take my antifreeze and oil and dump them around my garage to keep the weeds down.>

You're killing me Swanny, at work, we spent $1200 last month getting rid of 15 gallons of aqueous based parts washer solvent. I guess I should have asked you how to get rid of it.

We usually just dilute acid to a level where it is no longer HAZ.

'fenders

 

><i take my antifreeze and oil and dump them around my garage
>to keep the weeds down.>
>
>You're killing me Swanny, at work, we spent $1200 last month
>getting rid of 15 gallons of aqueous based parts washer
>solvent. I guess I should have asked you how to get rid of
>it.
>
>We usually just dilute acid to a level where it is no longer
>HAZ.
>
>'fenders


Fenders,

Swanny is probably doing it. That is scary. You know how contaminated the local wells around me are? Please dispose of fluids properly.

I aint no eviromentalist, but i gotta live too....

Robert

 

weeds? youll be keeping all living things down if you really just dump these things on the ground. im not a tree-hugger but some things just arn't right.

 

Robert

You are right. It all seems like an unnecessary inconvience until it's hard to find a drink of clean water. I think we should all do our part. The military now goes to great lengths to protect the environment. I was told during my initial HAZMAT training that the military participated in ocean dumping until 1980 due to their EPA exempt status as a goverment organization. Did not stop until 1980??? Isn't that unreal, we are smarter than that.

'fenders

 

whats the difference between me trying to kill a few weeds at a time, to the farmers dumping their stuff all over their fields by the gallon at a time.
im in the city and away from the wells.
i know it might get to the wells.
all im trying to do is get rid of a few weeds and alittle stuff at a time.
not like i change my oil and antifreeze every day.
im not that rich.
im not rich at all.

swanny

 

[updated:LAST EDITED ON 15-Dec-02 AT 10:42&nbsp;PM (EST)]<whats the difference between me trying to kill a few weeds at a time, to the farmers dumping their stuff all over their fields by the gallon at a time.>

Swanny

Not much actually. One of the above is legal and should not be. Finding a balance between profitable business and screwing up the world forever is a tough one. The farmers are much more regulated than you realize now. Most of their products are non-residual now. Sorry if you feel like your getting beat up. If you check around, I am pretty sure your community can tell you how to get rid of your oil etc. for free.

later
'fenders