I bought the Simple green spray in the clear green bottle. It did a good job in removing dirt from the engine compartment, but it couldnt remove the dark gray rust like off the power steering pump, throttle body , etc. it didnt even budge the rust under the 2002 accord hood. any suggestions?
Engine compartment rust and corrosion remover
- Thread starter Bluj40
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I'd use a power washer. The ones at the car washes are pretty weak so if you know somebody with a big diesel fired 220 Volt blaster go with that. If you don't get thrown back several feet before you get a chance to lean against the force of the water it ain't big enough.
You should repair the rust damage and then get the car oil sprayed after that. If you've got rust under the hood you've probably got more rust infront of the rear wheels.
Steve
You should repair the rust damage and then get the car oil sprayed after that. If you've got rust under the hood you've probably got more rust infront of the rear wheels.
Steve
Kestas
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The only thing that'll remove rust is a sandblaster.... Simple Green or powerwashing won't. I agree that it would help to apply some type of rustproofing compound on rusted areas to keep it from spreading. Beyond that, I've rarely found it fruitful to deal with rust on a car. It only returns in a short while. It's best to think ahead and rustproof a car - such as when the car is new - well before rust sets in. Otherwise, leave it be and spend your energy elsewhere.
Some of the parts you mention are zinc/aluminum alloys or "pot metal".
The gray stuff on them isn't going to wash off with anything - it's not rust but it is corrosion.
If you clean that away, you wind up with pits.
The only inexpensive way to do anything with it is a careful cleaning and spraying with an enamel made for the purpose or cold galvanizing.
On restorations you disassemble, sandblast, build up, polish, and recoat pieces, replace them outright, or creat copies if the car is worth it and the part unavailable.
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Well, usually the underlying metal is already "infected," even if you can't see any traces of rust. Cutting the rusty piece out is really the only "cure."
Phosphoric acid (Jasco sells a "metal etch product") will aid in the surface removal of rust.
Fish oil based primer works alright for delaying the progression of rust, so does a coat of raw linseed oil.
Surface rust can be removed with naval jelly, which is an acid in a jelly substrate. You can get this at most auto parts/autobody shops.
Permatex makes it...and I'm sure others do too.
Permatex makes it...and I'm sure others do too.
Kestas
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Can you please explain this. It doesn't make sense to me.
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Imagine the metal surface on a smaller scale. It's rough and has microscopic fissures. Removing all rust is practically imopssible. Ask at a reputable body shop what they think of removing rust 100% by sand or beadblasting. Rust is like the Terminator -- it'll be back.
Kestas
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I don't have to imagine it - I'm intimately acquainted with steel surfaces through the work I do. I've been looking at steel surfaces under the microscope for over 20 years.
Removing all rust via sandblasting is easy. This is how people restore automotive components. I do it regularly on my old cars. Sand blasting removes all rust and leaves bare metal, except for a few stray microscopic particles of blast media embedded in the surface. If anything, the surface is a bit rougher and can mechanically hold the paint better than the original smooth surface. Plus there's a slight peening effect on the surface to impart some beneficial residual compressive stresses.
I imagine body shops don't practise this sandblasting technique because it makes such a ***-awful mess. The sand gets everywhere, including the operator. Cleanup takes considerably longer than the actual sandblasting process.
Yes, the rust will be back... for the same reasons it formed in the first place... perhaps even quicker, because it is difficult for the DIYer (or body shop) to duplicate the wonderful anticorrosion treatments and coatings OEM uses on their vehicles. For starters, phosphate coating bare metal before painting goes a long way in providing a superior paint job that won't flake off. How many people do you know that use a phosphate coating before painting bare steel? I regularly sit in presentations where suppliers are touting new technologies in anti-corrosion systems.
Removing all rust via sandblasting is easy. This is how people restore automotive components. I do it regularly on my old cars. Sand blasting removes all rust and leaves bare metal, except for a few stray microscopic particles of blast media embedded in the surface. If anything, the surface is a bit rougher and can mechanically hold the paint better than the original smooth surface. Plus there's a slight peening effect on the surface to impart some beneficial residual compressive stresses.
I imagine body shops don't practise this sandblasting technique because it makes such a ***-awful mess. The sand gets everywhere, including the operator. Cleanup takes considerably longer than the actual sandblasting process.
Yes, the rust will be back... for the same reasons it formed in the first place... perhaps even quicker, because it is difficult for the DIYer (or body shop) to duplicate the wonderful anticorrosion treatments and coatings OEM uses on their vehicles. For starters, phosphate coating bare metal before painting goes a long way in providing a superior paint job that won't flake off. How many people do you know that use a phosphate coating before painting bare steel? I regularly sit in presentations where suppliers are touting new technologies in anti-corrosion systems.
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Hmm, I'll have to take your word for it, as I'll have to take anybody else's word for what they claim. In the past, on my cars that had rust, sandblasting never succeeded in removing all rust, which would come back within a year. I'm specifically talking about the fenders on my Scirocco. The only thing that helped was cutting the rusty edges out and having new ones welded in.
Anyway, maybe I should have my Audi's grille beadblasted after all. I stripped it and it's quite rusty, so I was considering to just get a new one, which may be difficult to find for a good price locally (Sells for triple price in US). But if you say blasting it will work, I might give it a shot. Oh, and if the rust comes back, at least the surface has been hardened.
[ September 24, 2005, 10:02 PM: Message edited by: moribundman ]
Anyway, maybe I should have my Audi's grille beadblasted after all. I stripped it and it's quite rusty, so I was considering to just get a new one, which may be difficult to find for a good price locally (Sells for triple price in US). But if you say blasting it will work, I might give it a shot. Oh, and if the rust comes back, at least the surface has been hardened.
[ September 24, 2005, 10:02 PM: Message edited by: moribundman ]
Kestas
Staff member
15 years ago I sandblasted the rust on my 71 Cutlass before body work and paint. I brazed new metal on the perforated areas, then followed up with bondo, phospahate bare metal, prime, and paint. I've been driving it every summer since then, even in the rain. I have some bubbling where the corrosion used to be, but it's held up quite well for a DIY restoration - I couldn't expect any better. I think this car shows that sandblasting is a good method for restoration.
On the other hand, I sand blasted the corrosion on my winter car two years ago and it's back. This is the high wash area of the lower fender and it sees a lot of salt. Like I said, it's hard to duplicate OEM finishes. I'll be sand blasting it again, but it'll need some anticorrosion treatment like tar, which'll look like **** on a white car. But what can you do? The car is rustproofed, andt the corrosion I get is where the underbody meets the Class A finish panels - a no-man's land for corrosion protection.
I regularly sand blast automotive and other parts. I do it so often, that I'm considering getting a sand blast cabinet for the garage. I already have compressed air, gun, and an old, broken vacuum cleaner to vent the dust. I'm tired of using the sand blaster at work.
You say the Audi grille is steel? I haven't seen a steel grille since I don't know when. Usually they're plastic, pot metal, or trim metal (aluminum or stainless steel).
On the other hand, I sand blasted the corrosion on my winter car two years ago and it's back. This is the high wash area of the lower fender and it sees a lot of salt. Like I said, it's hard to duplicate OEM finishes. I'll be sand blasting it again, but it'll need some anticorrosion treatment like tar, which'll look like **** on a white car. But what can you do? The car is rustproofed, andt the corrosion I get is where the underbody meets the Class A finish panels - a no-man's land for corrosion protection.
I regularly sand blast automotive and other parts. I do it so often, that I'm considering getting a sand blast cabinet for the garage. I already have compressed air, gun, and an old, broken vacuum cleaner to vent the dust. I'm tired of using the sand blaster at work.
You say the Audi grille is steel? I haven't seen a steel grille since I don't know when. Usually they're plastic, pot metal, or trim metal (aluminum or stainless steel).
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It's an aftermarket Kamei grille that I bought overseas 9 years ago and I don't want to buy a new one here, because the price is outrageous. The frame is aluminum, the mesh wire is steel. The OEM plastic grille broke when a pine cone fell on it while driving when the car was only a month old. The grille simply pops out of the hood (has two locking tabs). Maybe I should try electrolysis for rust removal. It's not a very large grille:
Anyway, the original poster of this thread had rust in the engine compartment. That's not exactly a good candidate for sandblasting, with the engine in.
Kestas
Staff member
Practically speaking, I think only POR-15 would help Bluj40 with engine compartment rust. The best way to handle rust in his case is prevention.
Kestas
Staff member
You may run into problems sandblasting your grille. There may be little metal left behind the rust, plus sandblasting also removes metal. If done too aggressively, sandblasting can remove the entire thickness of the wire mesh.
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Beadblasting would be less aggressive, right? The wire mesh is about 1/32" thin.
I checked the price of the grille. It costs currently $49 Euros ($60) overseas but in the US the same grille goes for $149 plus shipping.
I checked the price of the grille. It costs currently $49 Euros ($60) overseas but in the US the same grille goes for $149 plus shipping.
Kestas
Staff member
Yes, beadblasting (glass shot) is less aggressive. It would peen the material rather than cut it. You can also play with the air pressure - 100 psi is too high, 70 psi should work, use 50 psi as a starting point.
Is the OP actually talking about rust? He says "dark gray rust like" (or did he mean "dark grey rust, like...").
If so, it sounds like what I have, I think caused by castrol super clean or some other engine cleaner I used years ago. Considering mine isn't rust, how do I get this off?
See my pics:
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2
If so, it sounds like what I have, I think caused by castrol super clean or some other engine cleaner I used years ago. Considering mine isn't rust, how do I get this off?
See my pics:
1
2
Kestas
Staff member
We're mincing words here. The generally acceptable definition of rust is iron oxide. Corrosion can not only be iron rust, but also oxidation of other metals. Then there's sulfide corrosion, but we'll stop here.
I think Bluj40 was somewhat loose with the vernacular and he was talking about the same corrosion you are with the images you posted.
Brian, what you showed in your images appears to be corrosion of "white" metals, such as zinc or aluminum. Yes, Castrol Super Clean could have cause it. This product is essentially lye, which is highly corrosive to aluminum. If you use this product, it must be completely rinsed off. Sometimes it may need to be neutralized with a mild acid (perhaps citric acid?).
The only way to remove corrosion is by mechanical means... wire wheeling or grit blasting. There are no practical chemical methods of removing this corrosion. It is just like rust.
I think Bluj40 was somewhat loose with the vernacular and he was talking about the same corrosion you are with the images you posted.
Brian, what you showed in your images appears to be corrosion of "white" metals, such as zinc or aluminum. Yes, Castrol Super Clean could have cause it. This product is essentially lye, which is highly corrosive to aluminum. If you use this product, it must be completely rinsed off. Sometimes it may need to be neutralized with a mild acid (perhaps citric acid?).
The only way to remove corrosion is by mechanical means... wire wheeling or grit blasting. There are no practical chemical methods of removing this corrosion. It is just like rust.
Brian, the finish on these parts is minimal to start and is probably gone now.
I'd use a soft wire brush, fine steel wool, scotch-brite, whatever works.
Then paint..or just polish the metal.
I am also faced with this task - corrosion looks horrible...
I'd use a soft wire brush, fine steel wool, scotch-brite, whatever works.
Then paint..or just polish the metal.
I am also faced with this task - corrosion looks horrible...
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