What's the consensus on treating surface rust?

Raswan

Senior member
Jan 29, 2010
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Nabbed a 2001 Subaru Legacy with 162k miles yesterday for $3200. It's got maybe half a dozen of those real early pinpoint rust spots, but more importantly three 2-inch spots as well (one over each wheel well, as you might expect, and on the hatchback door). It's only flaking in one of the three spots. Other two are most definitely surface.

This car is primarily for Lowe's runs and during the deep winter in MN, and is otherwise gonna sit in the garage 28/30 days. I certainly don't expect it to last forever, but I'd like to at least stop the progression of the more serious spots. Willing to spend a bit of money and/or do some work on my own.

1. Wire brush to remove as much as possible + POR15 + paint?

2. Or Corroseal + paint?

3. Some other combination?

4. Or am I just better off bringing it to a reputable (e.g. not Maaco) body shop and having them take care of it?

Is the treatment the same for the pinhole rust spots?
 

mizzou

Diamond Member
Jan 2, 2008
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Doesnt sound like "surface rust". Honestly I feel panel rust is cosmetic as long as it doesnt affect the strucural integrity like a rocker in a ubibody. Im sure if you look underneath the subaru you will be horrified...

Why even bother fighting it if its already past the point of no return....Ive had OK results hitting the frame of my truck with a spray on rust converter. You can knock out the big rust with a wire brush before spraying.

I would oppose undercoating rust spots with rhinoliner. That stuff flakes off like no tomorrow and might even make rust worse.
 

Raswan

Senior member
Jan 29, 2010
702
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Doesnt sound like "surface rust". Honestly I feel panel rust is cosmetic as long as it doesnt affect the strucural integrity like a rocker in a ubibody. Im sure if you look underneath the subaru you will be horrified...

Why even bother fighting it if its already past the point of no return....Ive had OK results hitting the frame of my truck with a spray on rust converter. You can knock out the big rust with a wire brush before spraying.

I would oppose undercoating rust spots with rhinoliner. That stuff flakes off like no tomorrow and might even make rust worse.

Yeah, I'm under no illusion that it will stop, but unless something catastrophic happens this car has another 100k in it, and Minnesota tends to be a real bastard once the rust begins. The underside definitely has some rust, though honestly not as bad as I expected. No way I'm crawling under there and spraying it all.

What kind of spray-on rust converter do you use? Do you put any protectant (paint or otherwise) on after? I'd at least like to throw a little effort at it and see what happens. The rust on the hatchback door looks like it started because the previous owner always gripped that part of the door in the exact same spot. Probably rubbed off the clear coat and a few layers of paint after years of repeated use. It's really not that bad, though I understand that once the rust begins it never ends...
 

JCH13

Diamond Member
Sep 14, 2010
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If you've got pin holes then the metal is already tragically thinned out. If you wire-brush near pin holes you'll find out just how thin everything is getting (and maybe that's a good thing). If you don't a crap for a 'pro' fix, just scab over with whatever you've got handy. If you want something nicer, take it to a body shop.

This might be a great candidate for a tech school. They will repair and paint for the cost of materials. Not a pro result, but quite inexpensive.
 

Raswan

Senior member
Jan 29, 2010
702
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If you've got pin holes then the metal is already tragically thinned out. If you wire-brush near pin holes you'll find out just how thin everything is getting (and maybe that's a good thing). If you don't a crap for a 'pro' fix, just scab over with whatever you've got handy. If you want something nicer, take it to a body shop.

This might be a great candidate for a tech school. They will repair and paint for the cost of materials. Not a pro result, but quite inexpensive.

Thanks JC. The tech school idea is a good one. There are a few around here, and I'll check them out.

I misspoke regarding the smaller spots. By pinhole I just meant very small spots of rust. Nothing that goes through the body panels or anything. Just those kind that you tend to see on the front from a pebble that chips away at the paint and clear coat and then just begins to rust.

I bought a small variety set of drill-compatible wire brushes to clean out the bigger spots, and decided to give the Corroseal a try. Fingers crossed.
 

thedarkwolf

Diamond Member
Oct 13, 1999
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I've had good luck with por15 before in the past so if I were going to do anything I'd go that route. Have the headgaskets been changed yet? Assuming this is the 2.5l that would be my bigger worry if they haven't.
 

Raswan

Senior member
Jan 29, 2010
702
6
81
I've had good luck with por15 before in the past so if I were going to do anything I'd go that route. Have the headgaskets been changed yet? Assuming this is the 2.5l that would be my bigger worry if they haven't.

Thanks, I'll grab some POR15 as well. Can't hurt to have both on hand. Headgaskets were changed by the dealer before going on the lot, yep! Sounds like you know a thing or two about it--any other big fixes I should be aware of coming down the pipeline?
 

thedarkwolf

Diamond Member
Oct 13, 1999
9,000
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Thanks, I'll grab some POR15 as well. Can't hurt to have both on hand. Headgaskets were changed by the dealer before going on the lot, yep! Sounds like you know a thing or two about it--any other big fixes I should be aware of coming down the pipeline?

Years ago I planned to buy a Subaru from around that year and did a lot of research. The only thing I remember is the head gasket issue.
 

Pacfanweb

Lifer
Jan 2, 2000
13,149
57
91
Ospho, then put touch up paint over it. If you already have actual rust holes, doing it on the outside isn't going to stop it though.
 

Mandres

Senior member
Jun 8, 2011
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$3,200 for a rusty 20-year-old subaru with 180k on it? What am I missing? does this model have a cult following or something?
 

RLGL

Platinum Member
Jan 8, 2013
2,074
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surface rust on something that old.....waste of time trying to cover up