Author Topic: Rust on exhaust manifolds  (Read 1219 times)

hihorse

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Rust on exhaust manifolds
« on: June 14, 2022, 01:29:59 PM »
Is evaporust safe to use on exhaust manifolds?

Sauron327

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Re: Rust on exhaust manifolds
« Reply #1 on: June 14, 2022, 04:44:02 PM »
Why not? I just toss them in my cabinet blaster or use my pressure pot when doing big jobs.

hihorse

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Re: Rust on exhaust manifolds
« Reply #2 on: June 14, 2022, 05:21:30 PM »
I only ask because I ruined a nice set of manifold's using muretic acid.

x66 714

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Re: Rust on exhaust manifolds
« Reply #3 on: June 14, 2022, 06:10:46 PM »
Evaporust is the best. Knock off the loose stuff with a brush first. Works great....Joe
See America's First, Chevrolet

1968 Z/28 Corvette Bronze. Black Hounds Tooth. 02E Los Angeles born 3/13/1968 pnt OO. Purchased March 1976
1969 SS396 Yellow/Yellow 08E Norwood born 8/28/1969 pnt 76E. Purchased April 1981

Petes L48

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Re: Rust on exhaust manifolds
« Reply #4 on: June 14, 2022, 10:16:50 PM »
Muriatic acid is a diluted form of hydrochloric acid, but still pretty nasty stuff.  Evaporust is much less caustic and easier to work with, and eventually dispose of.  You can get creative and use a heavy duty plastic bag and ties for large parts, to minimize the amount of Evaporust needed.

Electrolysis is another option for rust removal, probably cheaper but takes a little longer and some additional supplies.  I've used this on pieces with real heavy rust. 
http://antique-engines.com/electrol.asp
   

z28z11

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Re: Rust on exhaust manifolds
« Reply #5 on: June 15, 2022, 01:19:18 AM »
I'd suggest electrolysis and passivate with Evaporust. You'll use less metal doing it that way - plus, it's cheap. Plus, you'll get the inside of the manifolds if you leave the electrolysis going long enough, followed by the Evaporust. Find you some Arm and Hammer Baking Soda detergent, a large enough plastic container, a good battery charger, and get to work. Actually fun to do - and effective.

Steve
1968 Z28 M21/U17 BRG/W 1967 Chevy ll Nova SS 
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06  1949 3100 5wd 235/6

HustleRussell

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Re: Rust on exhaust manifolds
« Reply #6 on: June 15, 2022, 10:27:35 AM »
When these castings were new, they were shot blasted in a Wheeabrator machine.
Russ 
68 RS
69 SS

Sauron327

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Re: Rust on exhaust manifolds
« Reply #7 on: June 15, 2022, 03:54:06 PM »
Muriatic acid should not be used on steel parts. I"m guessing most on these sites do not this everyday. Slight corrosion on the inside manifolds? Who cares?

CantRepeat

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Re: Rust on exhaust manifolds
« Reply #8 on: June 23, 2022, 07:17:58 PM »
Muriatic acid is a diluted form of hydrochloric acid, but still pretty nasty stuff.  Evaporust is much less caustic and easier to work with, and eventually dispose of.  You can get creative and use a heavy duty plastic bag and ties for large parts, to minimize the amount of Evaporust needed.

Electrolysis is another option for rust removal, probably cheaper but takes a little longer and some additional supplies.  I've used this on pieces with real heavy rust. 
http://antique-engines.com/electrol.asp
 

I have a plastic 55gal drum set up for this purpose using this method. It works great!! I've used it on a lot of Lodge cast iron pots and pans.
-Tim
67 RS/SS Vert C-1 797-Z LOS 11B
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firstgenaddict

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Re: Rust on exhaust manifolds
« Reply #9 on: July 03, 2022, 08:04:52 PM »
I am planning on a running a trial using CERACOAT on exhaust manifolds, I have thoroughly cleaned an exhaust manifold and will be blasting with garnet at 100# per ceracoat instructions.
Planning on mixing something close to a natural castiron look and also doing chevy orange for the flanges and bolts on Big block manifolds.
Looking for something to keep the appearance of a low mile survivor for a decade or more without maintenance. 
James
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70z28lt1

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Re: Rust on exhaust manifolds
« Reply #10 on: July 04, 2022, 11:03:30 PM »
I am planning on a running a trial using CERACOAT on exhaust manifolds, I have thoroughly cleaned an exhaust manifold and will be blasting with garnet at 100# per ceracoat instructions.
Planning on mixing something close to a natural castiron look and also doing chevy orange for the flanges and bolts on Big block manifolds.
Looking for something to keep the appearance of a low mile survivor for a decade or more without maintenance.
I used Cerakote C Series on a set, but have yet to start the engine.  You might try a 75-25 mix of Glacier Black and Glacier Silver.  I went 50-50 and its a bit too silver but I'm going to stick with it. It sprays very nice.  Did the front coil springs and going to do the leafs also.


rich69rs

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Re: Rust on exhaust manifolds
« Reply #11 on: July 19, 2022, 11:54:00 PM »
I did mine back in 2004.  Nothing fancy - pretty straightforward.

1) Sandblasted
2) Treated with a rust removal/preventative product Eastwood had at the time called “OxySolve”.  Have no idea if they still offer it.
3)  Sprayed them with primer.
4)  Finished it if wit hi temp paint.

Held up fairly well - probably have 10,000 miles on the engine since.

Richard
Richard Thomas
1969 RS