I am auto body ignorant and need some advice here. My floorpans have a couple very small spots that need patched however they appear that unless I get under there and stop the surface scale that's starting I may not have pans in a couple more years.

What's the easiest and most effective means to stop the rust and prevent it from coming back? Choices I'm looking at are either por15 or just the rust convertor from rustolium. I would like the end result to look pretty factory. Am I on the right track or is there a better product?

Any suggestions for a rattle can paint that matches the factory silverish coating? I don't have a compressor or spray gun access. This is going to be a fun job on jackstands with a wire wheel and naval jelly.

 

POR-15 will grab great to that. Wire brush it, blow off the loose stuff, then use a cheap paint brush on it. Make sure to wear gloves if you get it on your skin you'll be wearing it for 2-3 days.

If you want a super clean look paint it with POR-15 let it cure then do a rubberized coating on top of it.

 

Or spray on bedliner over the POR15/chassis saver.

 

I really want to avoid the rubberized under coat route. I just don't care for it. Aiming for a more painted finish. The car won't see much if any foul weather anymore. It's retired from it's daily driver status. I'm really hoping to be able to save the car. It has started to rust pretty badly in spots over the last 5 years in storage. It will be a couple more years unfortunaty before I can do a full repaint. Right now I feel the car is overall borderline and I want to do my best to slow or stop what rust it's already forming though.

Does the por 15 lay on pretty thick?

 

Not super thick but it will bond and help keep rust from spreading.

 

Eastwood sells a finish that is supposed to look like factory E coat.

 

X2 on POR 15, it's perfect for that. It is a little thick, it will fill small pinholes. Make sure there is NO paint left where you apply it. Rust is ok after you remove the loose stuff. Follow the instructions carefully.

 

Have look at my build link in my sig (last two pages).

I used POR 15 on my chassis components (k-mem and a-arms) and Duplicolour Bed Liner on my underbody, trans tunnel and frame rails.

Both work great.

The Duplicolour also comes in a spray can

 

Well I'm at a toss up. The POR 15 states that you have to apply it to bare metal. I don't have the means to sandblast or anything. That would take some extensive work with a wirewheel to get off the remaining paint in the non-rusted areas. I would hate to have this stuff peel off in places, and it would seem that doing this project again would be a nightmare.

I have used Eastwoods Rust Encapsolater in the past on my '69 birds subframe and it coated thick and evenly and worked great. But now the reviews on Eastwood's website all seem to indicate that they have changed the formula and it's not as good as it used to be.

I also found this stuff called Rust Bullet. Seems cheaper and states it's UV protected, no need for a topcoat, and can apply over paint or bare metal. Anyone have any experience long term with this? Does it hold up well?

Again, unless you still take the surface down to bare metal, and neutralize the rust. Then I would seem to think rubberized undercoat and bedliner would trap moisture and cause serious issues. I wouldn't be as opposed to using bedliner if the pan's where solid.

 

Since that is more rust than paint, shouldn't take that much work with the wheel and maybe some stripper. I agree that if you aren't going remove the paint, don't bother with POR 15, the paint will just make it bubble and peel.
I've used eastwoods rust encapsulator, but not on anything with that much paint on it. It's really more for things that were either unpainted to begin with or have little paint left.
I haven't used rust bullet, but I can't imagine any product will endure with that much paint that clearly has that much rust under it already. I really don't think you have a choice, you have to get that bubbled paint out somehow.

 

I just bought a gallon of this stuff for my rear end and sway bar, other rusty suspension parts. This stuff is awsome. I agree with stelth though that you should try to get as much of that paint off as possible. Looks like it will flake right off anyway and whatever you dont get you can always touch up later if some of the old paint bubbles.

http://magnetpaints.com/underbody.asp

 

Don't bother with Rust Bullet... I did the entire body of my 87 in it and it's now been melted down (most likely). It DOES NOT adhere to paint, even with prep according to their online instructions, and it seemed not to like even bare metal, also (cleaned with both a flap wheel and wire brush on a grinder). If my power washer could take it off, imagine what would happen at a touch-free car wash . The black didn't adhere well to the silver as another slap in the face, either (also prepped according to their directions to the last period). And that is called $370 down the toilet (4 quarts silver and 2 black). Reason I scrapped the body was because there was rust that somehow formed under their recommended coats of RB that SPREAD, eating through the rear of the driver's side floor pan. And I didn't have any way of using my welder without spending the equivalent of a new car on having the house and garage rewired for a new 20A circuit.

Get a wire brush for an angle grinder and get to work under there. You will be surprised at what you can get with a plain wire wheel. Once the crap is off, you will be able to better see what you've got to work with.

 

Well Athe great super awsome news is that theres no holes in my floor pans! They're actually more solid then I thought.



The really bad new is that while I was laying on my back looking up, I noticed the factory undercoat in my back driver wheelwell looked to be severly cracked and pulling loose. So I grabbed ahold and pulled the chunk loose and found a very deperessing sight.



I feel like I just got kicked in the nuts! This makes me want to just stop working on the floors.

 

Front, drivers side wheelwell.






So, needs a drivers door, drivers strut tower, drivers rear wheelhouse, passenger side lower quarter where spare tire is, and trunk panel. Guys I think this car is boned. I'm thinking it's time to find a roller.

 

Well a good friend just cured my depression as far as the rear inner fenders with a simple idea. "Dude you now have a good excuse to minitub it." Damn skippy! I might be making a call to Wolf racecraft. 315's? Yes please. After all my dad's a TV repairman, he has ton's of tools.

 

Dont get discouraged. Although rust is our enemy for sure, those spots can be fixed with some metal and a welder. Trust me I know all about fighting rust... but the good news is you CAN win the battle. If you take on the task of fixing the holes you have to make a promise to your 3rd gen that he or she (lol) will never see a drop of rain or snow again... Your car will love that idea. Find it a nice home in a garage and go to work.

 

I appreciate all the advise everyone. I'm just going to keep soldiering on with it. After thinking about it over a couple beers, the floors and frame after all are solid. The front strut towers are going to be the worst of the repairs. I just had an overwhelmed moment.

Ordering some POR 15. Got through alot of scraping and wire wheeling tonight.

 

Wish I had them tail lights and center piece. They look flawless.

 

Anyone every tried bed liner? That is what i am getting on my floorboards. Should i spray something on before i spray on the bed liner?

 

Use the POR15 Marine Clean AND prep/etcher for best results and wire wheel as much paint off as you can.

I went thru the same issues in my wheelwell and shock towers. Ending up cutting out the areas, welding in new metal, grinding and painting. Cant tell where the holes were.

I also removed and applied new seam sealer in the wheelwell are applied bed liner (Duplicolour) to cover and protect.

Sure did (see build thread in my sig- last page). Make sure you scuff the area with sandpaper (I used 180 grit) and wipe down before applying. Bed liner does not like a smooth surface.

 

My front drivers shock tower appears that the entire top will need to be cut off and replaced. It's two layers of steel and the entire inner/wheel facing layer is gone, or about gone around the entire upper strut mount. Might be a PITA to find a donor car for this; But it's not like I have alot to lose in trying to fix it. Might try 3rd Gen Ranch.

Procrastination payed off though. I waited a couple days to decide on what to do for a rust coat and Eastwood now has a 20% off sale. I ended up buying two POR 15 starter kits for $35! Figured that way I have two sealed can's one for each side, that way the crap will be less prone to drying out on me. Hope they get here before my next day off.

As for the back fender wells, GM has the inner wheel houses for $275 a side. Wolfe Racecraft has the mini tub kits for $140 and currently is having a 15% off sale themselves. This is extreemly tempting.

I'm torn here though because I don't want to lose my backseat and belts and am only looking to fit a 10.5" wheel max. Although, I'm going to be putting in an 8pt and not sure if I want the kids riding back there with a cage anyway. So I'm going to strip the rest of the undercoat and see how bad the rust is spread and go from there.

 

Don't order POR-15, what is it with this site and slathering that **** on everything? This site and this site only, I swear.

 

Yeah, don't listen people telling you to do things the hard way, get some bedliner and roll it on. Tired of people trying to turn this site into something to be proud of.

 

There's nothing to be proud about a car slathered with thick black crap used for rolling over rusty marine hulls.

Fix it right or don't bother, this site is depressing. It's like if I want to read about cars, I go to other forums. If I want to read about piles of junk getting $3 half-*** fixes, I come here. I can only take so much I guess.

 

Dude, Seriously WTF? What I hate is coming here and posting, and without fail getting a crap load of troll *** responses from people who have nothing positive to contribute to the topic. It really does get tiring. Maybe you can post exactly what you feel would be an appropriate way to go about this then? Instead of just being negative. My post title didn't exactly read "come in and see a 50-75k build now did it?"

Trust me I would like nothing better than to start pulling the car apart to be media blasted and sent in for a 7k+ paint job. However we are getting ready to buy a new house in the next year and that has to come first. Currently the car is stored 45 mins away from us at the rents house so even time and space to work on it is difficult. When I have my own garage to put it in, then it is getting ripped completely apart for a 100% proper resto. Trust me this car is my baby and I want to see it done right. It really pains me to see the rust it has in it right now. Untill then, i'm trying to do what little I can.

In the meantime I have to stop the rust in the pans otherwise it is going to cost me an arm and a leg to weld in new pans among the rest of the expensive body work I'm already looking at. And for clarification, I already stated that I wouldn't be using bed liner under my car or rubberized under coat. I appreciate the suggestions however I personally don't like a goopy look.

I plan on wire brushing the loose stuff, then completely sanding the entire floor. The transmission is coming out for a T56 swap that I already have, so everything is going to be taken down and done completely. The rearend has to come out and be replaced because the BW is junk, so even the gas tank is coming out to get a 255 while it's apart.

I felt that the POR 15 would help level some of the pits and would neutralize what little rust will be left after prep, seeing as I don't have the means to media blast, and I plan on primering and topcoating it with a dark grey paint. I already have about 6 hours in of sanding on just the drivers side pan.

Nothing to this point has ever been half assed on my car.

 

My post was more geared toward this site and its general championing of the use of POR-15 for anything and everything, and for the crap fixes 99% of the cars on this forum get; it wasn't directed at you specifically.

If I were you, I wouldn't do anything with it if you are truly planning on stripping it down and doing a full restoration later. I've seen cars far, far worse get full blown restorations (mind you no third gens) so a little scale on the floor pans shouldn't make too much of a difference if in the end you're going to tear it all apart. Why make it harder for yourself later, do you have any idea what a mess POR-15 will be when the time comes to do a full restoration? You'll wish you hadn't done it.

If the car is not a daily driver, and it's stored in a dry place, the rust won't spread. Leave the car as it sits until you can do it right, the floors will still be there.

Don't slather it with POR-15 "for now" like everyone else does. Let's be honest, 99% of the cars on this board that get the POR-15 treatment were half-baked projects to begin with by people who had no money or business trying to build a car, and ended up in the junkyard. Don't be a statistic...don't be yet another third gen that gets the POR-15 treatment on its way to the junkyard.

Don't mess with it. Keep your priorities straight, if you are buying a house, buy a house and don't put a damn dime into the car until the time is right.

 

Well, that's just it. Every time I go over to look the car over and start it, the rust has spread and is getting worse. In 5 years the car has gone from rock solid and rust free, to "Holy wtf happened!" Seriously, the pan's had one little tiny spot on them when it was parked in storage. And this is in a dry garage. And now they look like the pic above. I don't want to have to weld in new pans just because I neglected the surface rust on these pitted but otherwise solid ones. It will probably in all honesty be a couple more years before this car would go to paint. I was hoping to have the sense of accomplishment that when it does go to paint that I can consider the underside already done. I've been otherwise stockpiling parts for when I have the space to tear it completely apart.

That's essentially why I started the post though. Because I don't want the underside of my car to look like a "tar pit". I've never worked with POR 15 before so I have no idea how the end result looks when applied. If you say it will look like crap then I don't want to use it then. Can anyone link me to some pics of it done? At this point I've already sanded quite a bit to bare metal so "something" has to go on it.

I was assuming it would self level and apply pretty smooth and thinly "unlike undercoating."
Last time I used Rust Encapsulator; I applied it in a couple thin coats with a foam brush, then top coated it and it came out looking really good, didn't look the least bit gobbed on and had no brush strokes.

Now I'm not aiming for a perfect concours show car here either though, this car is far past that point, and simply buying a low mileage car would put me light years ahead of the game. I just want it to be at a clean level I can be proud of.

 

Just because lots of people use POR 15 improperly doesn't mean it's bad. By that logic, all paint is bad. I and others posted that it is perfect for the floor pan problem you were originally dealing with. We did point out that just "slathering it on" wasn't going to work.
However, your problem has now progressed beyond POR 15. I agree it would be pointless to protect your surface rusted floor pans while your front end has already rotted out.
At this point the body's integrity is compromised. Only options I see at this point are a complete strip with lots of welding or start looking or a better body. Even by my very northeast standards, that's pretty bad.

 

Oh and BTW, it didn't go from "rock solid" to that in 5 years (unless it has seen regular winter salt driving). this is a great example of how unibody cars (and maybe PO) can hide major rust without a very close inspection.
If it has been driven reg in winter salt, well, that's why you shouldn't do that.
This type of unibody has very little underside protection. Salt gets in everywhere and then the cancer starts.

 

speaking of things im tired of is people coming into every thread and bashing people trying to fix their car. not everybody has a low mile unmolested rust free car. not everyone has unlimited funds. but we all here love third gens and this site should be about supporting people. if you dont like what you see in a thread hit the little x in the corner and keep your mouth shut!

 

It has been parked, and trust me there was no "visible" sign of rust on that strut tower 5yrs ago. The strut tower can be replaced/repaired. The frame and floors is solid and otherwise the car has no structural issues. It apparently has been rusting under the undercoating. Proof that the crap traps moisture and induces rot.

So by your standard I should let the floors rot out because of a 12" square patch of metal on one strut tower. Genious!

 

Thank you solaris!

 

Here are pics from this week btw. Notice how far gone the car is...sarcasm

 

I agree to a point, if you are going to do a full resto on the car do not go the POR 15 route for future cutting and welding. As far as the scale spray it or brush it with a rust inhibitor (Gels or liquids, Ospho) and then use a good epoxy primer to seal it off. I would start by fixing the structural stuff like the strut tower and then go onto the rear; the trick is not to become overwhelmed with the entire job. I can tell you from experience that people (dishonest ones) find this stuff on their cars and slather on thick undercoating and POR15 and then sell it off to the next person, as far as this site goes, well..... There is a lot of negativity, but that is just common you know that, the problem with third-gens is that they can be bought cheap and a lot (not all) of kids destroy them with the cheapo upgrades that do not do crap. HP = $$$, there is no way around it, buying a TB spacer and a K7N air filter is nothing. Body work and good paint cost money, Rustoleum is cheap and looks cheap, it’s all about your priorities, but I agree if you cannot afford to modify or paint your car than just be content with it until you can afford to do it correctly.

 

I don't say you should let them rot out, just don't see the point of slowing down the rust there with expensive materials if you 1) aren't going to fix what I think is a more immediate problem 2) take the time to actually strip the paint first, didn't sound like you wanted to do that.

I suggested the alternative of getting a new body because the damage you showed is going to require removing a lot of stuff to properly fix. In the cars I have seen, the damage you show usually indicates more hidden problems somewhere else. As you said, the rust was hidden under paint and undercoating, but it WAS there. It has been my experience that the kind of rot you are seeing was caused by salt exposure, which means its very likely to be doing the same thing elsewhere.
I fully endorse repairing your floor pan damage with PoR 15, I just pointing out that you might be wasting time and money fixing a small problem when much larger ones need attention. You might get some more parts off to find even worse rot, in which case you will save some effort finding a better body. I know many people think we should save every third gen, I'm just not that sentimental. There are still tons of these cars around, sometimes it's better to start with a better base.
If you are dedicated to saving that body no matter what, fine, but I would just forget the pans for a while until you have a chance to get deeper into it. For example, the first thing I would do before that is pull up your carpets and see what the other side looks like. I would feel pretty silly if I spent a bunch of time and money doing those floors to find the rust even worse on the other side, possible with the frame rails or foot well corners completely rusted. I have made that mistake before.

People should make what ever repairs they can afford the time or money for, but even the most basic repair can be a waste of time if it doesn't address bigger issues.
I hope you get lucky and the damage you show is the worst of it, but I wouldn't bet my time and money on it without further investigation.

 

My thoughts are that when someone posts a problem that they need help with, we should be willing to give help based on past or current experience and not use this post as a site to complain about things on this forum that we don't like, members that we don't like, or methods that have been used by others that we don't like. Where is the help in that?
While I have no bodywork experience to offer any help at all to the OP, I do enjoy reading about problems like this and seeing how they get resolved. I just don't enjoy all of the nit-picking and belly-aching that some malcontents feel the need to post.

 

Those strut towers are bad. I saw less rust in that area on a firebird with 358k miles last weekend in the junk yard. That being said I've never done a tower swap, but I would make sure to get it very rigid. Remember they have a lot of stress from the struts on them. If you look around someone here actually did a tube chassis front end mod few years back. That might be interesting with your minitub project.

 

Alright, lets clear the air here then we can move on...

First off, I appreciate again all the constructive comments. I have been able to find a couple pic's of others' projects after using this on their pans and IMO it looks terrible, bubbly, uneven and a brownish tint to it. I wish I wouldn't have purchased it now but oh well, it was only $30. No big deal. I'm sure it can be used on something else sometime. Maybe my wife will use it on some lawn furniture who knows.

My primary question and the entire purpose of this post was to simply inquire about what the best product and method is to address my floorpans. I will not be leaving them another two years to continue to let a minor surface rust issue fester into a full blown need to replace the entire pans.

Secondly, Everyone is jumping to their own conclusions that things will get half assed. I made no remarks to indicate that I would slather POR over rust holes and just hide major issues. I have access to a MIG welder and myself and friends are competent in using one.

Third, I am fully aware of the structural importance of the strut tower. I have seen half assed fixes cause struts to go throught the hood before. I assure you the factory did weld these in originally, collision damage has caused probably thousands of them to be replaced before, and mine will be fixed properly. I have even entertained the idea of tieing the cage through the firewall and into the towers to help stiffen them.

Fourth, I am fully aware of my budgetary limitations and didn't ask for an assessment of if the car should be scrapped or saved. So lets not turn this into one of those posts. I have a firm grasp of where I draw my limit and how much I'm willing to tackle. That said, this car is far more rare than most Corvettes that people pour thousands into. I might see a Formula 350 on the road in my area once every three years. I will continue to tear the interior out and try to further assess if there is any more damage. I feel that if it costs a thousand or two more to save it, so be it. I have owned the car for 10 years now.

If I deem it too far gone I wil find another shell, It's that simple and not worth the energy wasting yet another post discussing about it.

I have removed the undercoat from the passenger side tower and it is 98% solid with only one very tiny spot of rust. I have also crawled all over underneath the car and the torque box's are solid and rust free and there is no thin spots in the pans that I can see, overall they seem completely, structuraly sound.

So going forwards I will forgo the POR 15, continue to sand, primer, and paint them instead. Hopefully it will slow/stop the rust from worsening until the car can be media blasted.

 

Best of luck with your project! Please keep the posts coming. I'd like to see it completed.

 

I've been using POR15 on all my vehicles for the last few years especially on parts like radiator mounts, battery trays, etc. and spot repairs. If prepared/applied properly, it DOES keep the rust from spreading. Of course if the affected area is too far gone then the only option is to cut and weld....but good luck....don't let the haters on this site stop ya..

 

Cool, but just remember to use a rust inhibitor (like acid) before you prime to stop the rust, good luck brother and keep us posted

 

I just received my POR kit's in the mail today and it comes with their "Fast Etch" prep. I'm def still going to be using the prep stuff that comes with the kit. Now all I need is another free day off work. Been working 10.5hr days all week on mandatory overtime. Ugh...

 

I feel your pain, last thing I feel like doing when I get home is crawling under my car. Now that the weather is cooling off a little bit it is easier to get into the work again, I plan to spend all day Saturday on mine. I wire wheeled my entire underside and usd Ospho, then I sprayed it with epoxy flat black and it just looks clean not drippy or gloppy, good luck

 

One side done. Won't be popular but I went with gray. Makes it easier to see under the car when your working on it.

 

Looks nice. I'm definitely looking forward to see the wheel tubs and front end repair.

 

I'm going to be cleaning my floor pans this weekend and was thinking about treating it with POR-15 as well...I'll post more once I start working.

 

I have some scale rust on the underside of the floors on my formula, I might try some POR-15 on them, it looks like yours turned out good.

 

I layed POR 15 down over the rustiest bare parts. Once it tacked up I sprayed some primer over it and then top coated it with dove gray enamel from Lowe's. I'm pretty happy with the results. I would have prefered a little but darker gray.

 

I got that spot on the spare tire well on the bottom that I think i'm going to wire wheel it clean and put some POR-15 on it. I also saw your shock tower area rust, I recently got a 1987 IROC-Z thats been around the Springfield area for awhile and it's having the same problem. Springfield never fails to salt the roads lol!

 

Do yourself a favor, take out the wheel liner and scrape out the undercoat. Mine was way worse than it first appeared.

While the liner is out, look back into the fender towards the drivers side footwell on the firewall. It's another common hidden spot for rust. Debris falls back along the inner strut tower and collects there holding moisture.