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Paint and Body How should I treat this hard to reach rust

  • Thread starter Thread starter AnthonyA1234
  • Start date Start date Feb 23, 2025

AnthonyA1234

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#1
  • Feb 23, 2025
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Was working around the ECU and I noticed above it I got some rust going on. I had metal work done on the car there and it looks like where the welds burned through to the other side and left bare metal it caused rust. It’s pretty deep in there and hard to reach how would you guys treat that?

I have a bottle of OSPHO I was thinking putting it in a spray bottle and jet streaming it up in there but is that stuff safe if it gets on any of my wires?
 

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limp

wrap a little cheese around it and its a done
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#2
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Pretty sure OSPHO is just pool acid... It will not harm plastics....... BUT, after spraing it, I would wipe it down a couple of time with a damp cloth, dry it, then mask and paint it.....
 
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AnthonyA1234

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#3
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limp said:
Pretty sure OSPHO is just pool acid... It will not harm plastics....... BUT, after spraing it, I would wipe it down a couple of time with a damp cloth, dry it, then mask and paint it.....
Click to expand...
Do you have to paint it? Will the rust be stopped with just the ospho alone? I’d rather not paint it cause I’m scared overspray might get everywhere in my interior and exterior

I also don’t even know if I’d be able to get a spray can at the right angle in that tight space to shoot paint up there
 

Mcmahst

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#4
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Maybe a 1” wide, large paint stick with a very small paint brush taped to the end to at least, touch it up with paint?
 
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AnthonyA1234

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Mcmahst said:
Maybe a 1” wide, large paint stick with a very small paint brush taped to the end to at least, touch it up with paint?
Click to expand...
This is an option thanks
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#6
  • Feb 23, 2025
  • #6
Or spend about three hours and pull the dash. He says set a day aside but if you have basic skills which you do then it will not be a day.

View: https://www.youtube.com/watch?v=7fOh87IYUKU
 
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General karthief

wonder how much it would cost to ship you a pair
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#7
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Ospho is not 'just pool acid', it IS caustic but a chemical that reacts with rust turning it black once it's dry you should wipe down with thinner or wax/grease remover then a coat of etching primer then paint, otherwise it will start to rust again, not right away but soon.
 
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AnthonyA1234

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General karthief said:
Ospho is not 'just pool acid', it IS caustic but a chemical that reacts with rust turning it black once it's dry you should wipe down with thinner or wax/grease remover then a coat of etching primer then paint, otherwise it will start to rust again, not right away but soon.
Click to expand...
If I attempt fixing it without removing the dash id use a long brush like Mcmahst recommended. In that case I won’t be able to use spray cans so I can’t spray self etching primer on it. In the past when I’ve used ospho I’ve just top coated it with Eastwood rust encapsulator and that’s it. I never use primer. Is that wrong or will that work?
 

General karthief

wonder how much it would cost to ship you a pair
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#9
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AnthonyA1234 said:
If I attempt fixing it without removing the dash id use a long brush like Mcmahst recommended. In that case I won’t be able to use spray cans so I can’t spray self etching primer on it. In the past when I’ve used ospho I’ve just top coated it with Eastwood rust encapsulator and that’s it. I never use primer. Is that wrong or will that work?
Click to expand...
I believe that will work just fine, I think Eastwood has a spray with a flexible tube spray head of some kind, check em out, I'd pull the dash to make sure I got it all taken care of. But that's me.
 

rednotch

I'd like to remain having one chocolate starfish
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#10
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AnthonyA1234 said:
Do you have to paint it? Will the rust be stopped with just the ospho alone? I’d rather not paint it cause I’m scared overspray might get everywhere in my interior and exterior

I also don’t even know if I’d be able to get a spray can at the right angle in that tight space to shoot paint up there
Click to expand...
If your worried about over spay use wool wax or fluid film then wipe off Areas that are still sealed by paint....
 
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Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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#11
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That way up in there. I don't recon' it's going anywhere




Spray it and forget about it until you have some other [good] reason to get back into that section.
 
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Mcmahst

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#12
  • Feb 24, 2025
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And if you don’t want to do the spray can, get the weld-through primer can, spray a puddle on a piece of plastic, and use that little brush and put it on. I’m not saying I’ve ever done that, but I’ve seen it done.
 
R

Rcdgl

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#13
  • Feb 25, 2025
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Eastwood makes a spray can with a long tube to fit in frame rails and similar places, try that. I used it on the front frame rails and the seat brackets on my 82.
 
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