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SuperHawk Jr
11-24-2010, 02:21 PM
Hello,

We have an intake manifold that was left outside a little longer than it should have been, and now the inside "waffle pattern" has surface rust on it. Before putting this on a car and having those rust deposits go through the engine, I would like to remove the rust as best as I can.

Does anyone know of a solvent or other cleaner that I can apply to the rust surface of the inside of this intake manifold to help aide me in removing the rust? I would prefer to find a miracle product that I could just pour in, or spray on and wipe / rinse the rust away with. Does such a product exist?

Please advise


Thank you,


-Superhawk, Jr.

DEEPNHOCK
11-24-2010, 02:33 PM
Nope.
Beadblast the snot out of it.
Do inside the heat crossover passage, too.
Clean it up, and re-paint it.
You will feel better about your intake manifold, and your self esteem.
HTIH
Jeff:cool:

PackardV8
11-24-2010, 02:49 PM
Bead blasting is for delicate. This is rusty iron. Suggest a coarser blasting medium, such as nickel slag.

Remove the carb studs and plug the holes with used cap screws. Immediately after blasting, blow it out with high pressure air, chase the carb pad holes and reinstall the studs and spray paint the outside to prevent flash rusting. I've had no problem painting the inside of the manifold also, but your results may vary. When the paint is dry. use a flat file to check the flatness of the intake port mounting surfaces. A few strokes will show if they are flat or need some Indiana machining.

jack vines

jnormanh
11-24-2010, 02:51 PM
You can get Naval Jelly in a liquid spray bottle. It will remove the rust in a few minutes.

sweetolbob
11-24-2010, 02:55 PM
You could also soak it in vinegar for a few of days. Relatively gentle and pretty effective for surface rust, also pretty cheap.

Bob

Deaf Mute
11-24-2010, 04:02 PM
... and what vinegar you don't use on the manifold... makes a good Thanksgiving salad dressing!
That said...
Whenever I blast anything... I cannot get all of the media out of it and thusly am very careful about blasting any part that goes on the suction side of my engine!

bsrosell
11-24-2010, 04:35 PM
I have had some success with Evaporust. Sounds like more what you described in your original post. I got it at AutoZone here in Minnesota, but here is the website if you are interested.
http://www.evaporust.com

DEEPNHOCK
11-24-2010, 04:43 PM
Well, you could use electrolysis, beet juice, cider, Naval Jelly, and on and on.
(BTDT)
My comment was based on having done a couple hundred intakes, and having tried about a dozen methods with various results.
For the best results, with the least effort and expense.. Sandblast/bead blast the snot out of it.
Sure, you have to clean it afterwords. And clean yourself, too (wear a respirator!)
If you get sand down inside your engine, something wasn't cleaned.
I think the salad dressing might be a bit gritty:p...
Jeff:cool:


... and what vinegar you don't use on the manifold... makes a good Thanksgiving salad dressing!
That said...
Whenever I blast anything... I cannot get all of the media out of it and thusly am very careful about blasting any part that goes on the suction side of my engine!

PackardV8
11-24-2010, 04:54 PM
Well, you could use electrolysis, beet juice, cider, Naval Jelly, and on and on.
(BTDT) Like Jeff, I've tried all the chemical treatments. They do work, but not as quickly or as thoroughly as blasting. At the machine shop, any part to be blasted goes through the parts washer first and air blasted dry. Any moisture, grease or oil will trap the blast medium. After blasting, the part is washed again, air-blasted dry and immediately painted.

jack vines

hank63
11-24-2010, 07:00 PM
Quick, efficient but a bit messy - use "brickies acid" (hydrocloric acid). Will make cast iron look like fresh from the foundry.
Warning, do not use on aluminum or alloys.
It's cheap and easy, but handle with care. It's rather aggressive.
/H

Pat Dilling
11-24-2010, 09:07 PM
Saw this stuff at the SEMA show. Demos were impressive on everything from sheet metal to engine blocks. Cost is about $15 for a gallon or $80 for a 5 gallon bucket.

http://farm2.static.flickr.com/1227/5150675877_5be4995096_z.jpg

Good news is it is completely non-toxic and biodegradable. The end solution is rich in iron and can even be used to fertilize your lawn.

http://www.metalrescue.com/home.aspx

jclary
11-24-2010, 09:15 PM
I have a suggestion but it is a little far-fetched for most of us. However, if you have a friend or know of someone with access to a vibratory finishing machine, that would be an excellent prospect for cleaning an intake manifold. It would have to be loaded with a ceramic media that would resist packing and binding in the inner passages but could do a thorough job of cleaning the inside and outside of a manifold.

Problem is, I have never seen one outside of an industrial setting or machine tool trade show.

tluz
11-24-2010, 09:45 PM
Eastwood makes a rust dissolver that is very similar to the evaporust product pictured above. It works very well, although heavy rust takes a couple of days of soaking to go away.

sbca96
11-24-2010, 10:53 PM
although heavy rust takes a couple of days of soaking to go away.

Wow, dont spill any on your Studebaker then! ;)

Tom

TXmark
11-25-2010, 12:59 AM
electrolysis is my vote removes ONLY the oxidized metal works very well on a manifold, simple efective and nota lot of work

DEEPNHOCK
11-25-2010, 06:30 AM
But electrolysis won't get all the hidden inside corners.
I built a stainless steel lined tank just to do intake manifolds.
It had the absolute best possible current path characteristics possible.
It was first hooked to a battery and a battery charger, and later to a WELDER (to maximize the electrolytic potential).
After a long session....it still left rust deep inside the manifold.
How long was your intake in the tank, Mark?tter... I was too impatient <lol>..
If you had a lot of time, maybe it would work be
If one were to insist on a chemical dip, I'd suggest the beet juice dip, or the molasses dip.
BTW... The industrial machine for blasting steel for paint prep is a Wheelabrator.
http://www.wheelabratorgroup.com/xq/aspx/ind.2/qx/industries.htm


electrolysis is my vote removes ONLY the oxidized metal works very well on a manifold, simple efective and nota lot of work

4961Studebaker
11-25-2010, 08:28 AM
I have a suggestion but it is a little far-fetched for most of us. However, if you have a friend or know of someone with access to a vibratory finishing machine, that would be an excellent prospect for cleaning an intake manifold. It would have to be loaded with a ceramic media that would resist packing and binding in the inner passages but could do a thorough job of cleaning the inside and outside of a manifold.

Problem is, I have never seen one outside of an industrial setting or machine tool trade show.



I know exactly what you speak of........only on a smaller scale, "media tumblers" (but don't tumble like a clothes dryer) commonly used to polish brass rifle/pistol cartridge's
granted, on a much larger scale for manifolds. : )

4961Studebaker
11-25-2010, 08:40 AM
For the life of me I don't remember the process name.......Expensive......and only cleanes the passages.

IIRC The injection of play-doh type material cleaned and could enlarge the passages depending on the media itself.

N8N
11-25-2010, 08:52 AM
For the life of me I don't remember the process name.......Expensive......and only cleanes the passages.

IIRC The injection of play-doh type material cleaned and could enlarge the passages depending on the media itself.

Are you thinking of Extrude-Hone?

http://www.extrudehone.com/

you're right, it's expensive...

nate

Aussie Hawk
11-25-2010, 04:23 PM
With my work I acid clean boilers, heat exchangers, cooling towers etc all time. I did a 150 Hp boiler last week, used 150 gallons of 30% Hydrochloric Acid, diluted to a 6% solution circulated for 24 hours. I'd use a 10% strength solution, mixed with hot water - (even HCL has a hard time removing iron oxide - rust), but when heated it does the job. Leave it for at least 24 hours. As a precaution cover the machined surfaces with some type of adhesive tape to stop any pitting. When done give a really good wash/flush to get rid of any remaining acid, soak in water with washing power, (it's an alkaline and will neutralise the surface of the metal and inhibit rust formation).

52 Ragtop
11-25-2010, 07:32 PM
Take it to your local dip stripper, and have them soak it in the paint stripper, then rust solution, it will come out spotless, and probably less than $20.00

Jim

PackardV8
11-25-2010, 11:44 PM
t

For the life of me I don't remember the process name.......Expensive......and only cleanes the passages.


IIRC The injection of play-doh type material cleaned and could enlarge the passages depending on the media itself.
Are you thinking of Extrude-Hone? http://www.extrudehone.com/ you're right, it's expensive..

CASOs need not apply to Extrude-Hone. IIRC, it is $450 for the treatment on a cast iron intake.

jack vines

gordr
11-26-2010, 12:59 AM
Electrolysis doesn't work well, because it is a field effect. It will do exterior surfaces of a part very well, but the interior surfaces don't "see" the electric field that does the work. Electroplating is much the same; plating doesn't "throw" very well to sharp cavities in the work.

Hydrochloric acid doesn't cut rust as well as several other safer and readily-obtainable acids. Both citric acid and phosphoric acid readily dissolve rust, but are quite gentle on bare iron or steel. I'd choose phosphoric acid, as it leaves a black iron phosphate coating that serves as a good binder for paint, and protects the metal somewhat against further rust. The metal prep products sold at autobody supply stores usually contain dilute phosphoric acid, but you ought to be able to get fairly concentrated stuff at a chemical supply house. As acids go, it's one of the less nasty to deal with. It's part of the flavoring in Coca Cola.

4961Studebaker
11-26-2010, 08:29 AM
Are you thinking of Extrude-Hone?

http://www.extrudehone.com/

you're right, it's expensive...

nate

Yep, that's what I was thinking of.

Neal in NM
11-26-2010, 10:01 AM
Use TRECAL it is very cheap but it does take time. I have used it over the years and it is fantastic. Neal

garyash
11-26-2010, 04:38 PM
I took a rusty manifold to my local FLAPS a few years ago. They used steel shot blasting to clean it inside and out. I was happy with the results and they didn't charge too much.