Modding Dreams Stopped by Rust

Hey guys,

Over this past week, I've been trying to 'fix' a rust issue on my rear wheel arches and interior side bottom of the passenger front door, which is also starting to rust bubble on the exterior side as well. I live in the snow / salt belt that is Canada, so this isnt avoidable.

I say 'fix' the rust, but I'm really only maybe slowing it down, only for it to rear its ugly head again in maybe half a year to a year if I'm lucky. The real fix is to replace the door and cut-out and reweld new quarter panels. The rust isn't advanced yet, so this isn't necessary at the moment, but it's the only true fix and who know for how long.

The car is a 2011 with 127,000 miles (204,000 km) and has been and such a pleasure to own compared to my previous car (2004 BMW 330i), which was a money pit. I guess I'm seeing that the Mazda is of that vintage that it will start becoming a money pit as well. (Please don't get me wrong, I love the car still, but after the experience with the BMW i vowed never to throw good money after bad in the name of vanity ever again).

I had plans to do a BNR S3 turbo swap and ordered some of the supporting mods (3 bar MAP sensor, bitwise wiring harness, COBB 3-port EBCS, and Forge V1 BPV) from Edge Autosport. I was next going to order an ATP 3" catted downpipe, and after that I would order the BNR S3.

With the rust starting on my car, I am going to halt any further mods, return what I can to Edge Auto and continue to drive it as is for the next 2 or 3 years, because sadly, the cars value isnt worth what I would put into it for a proper rust repair and the subsequent mods...and then who know about the longevity of the motor.

Anyways, this was kind of a dear diary post...a little disappointed about it, but it is what it is...reality knocked on my door this week.

Andrew

 

You could just mod it for the next couple years and then send it to the junkyard

 

Why not come to the US and find a decent chassis to swap everything good into. You can find decent sedan or hatch models down here with a manual trans for 2-4k and then just swap all your speed stuff in.

 

Restocking fee is not low. Modify. Slap POR15 and Bondo to get by.

 

EZ flares and negative offset wheels!
Because I have winter beaters in Canada while my fun cars are parked for winter I have had a lot of experience in this area.
If you have paint bubbles...not rotten sections...
You can sandblasted clean, from inside the quarter/dog leg plus the bottoms seam inside the door, and sand down on the outside. Once all corrosion is removed, then re-seam seal followed by recoating it well. I have had good luck with DOM16 (Dominion sure seal - Canadian version of POR15) on the inner panels and underside. It converts/sticks to rust and loves sandblasted metal. After coatings have cured (4-6 weeks) spray or poor chainsaw bar oil from inside where the wheel well meets the quarter panel. Allow it to run down the dog leg and back into the trunk drop down. Also spray it up through the door drain holes to the point it runs out. I also remove the trim across the bottom of the door opening and spray down into the rockers. Dont wash the car for about a week. Put the jug in the kitchen sink with hot hot water for an hour before spraying...also works best in the summer. I got a degreaser sprayer from Princess auto and you only need a small compressor to do it.
As for the exterior, NAPA metal pro paint is great. You mix it with thinner and hardener. I rolled my hood with it and wet sanded it down because wrap wont stick to primer. I would suggest wrapping the bottom of the car between the wheels in the same colour as your car once all the paint work is done but you wont need to wet sand it smooth unless you want a perfect smooth surface.
This would last at least 4 years if properly completed before showing signs again, probably longer. I did this on my winter Impreza (plus welded in 6" patches) 5 years ago. I just noticed this year a couple tiny paint bubbles and this car only gets used in winter and never gets washed. Reapply the Chainsaw bar oil yearly...in the future do this with your next car also from the day you get it.

 

@Raider, I'm applying POR-15 right as we speak and it's already failing.

I followed every step, cleaned the metal, used their degreaser multiple times, metal etched, rinsed thoroughly, let dry overnight and there is still a film or material preventing proper application. It's that, or it's the Krown treatment weeping through the compromised body seam.

That autobody supply shop f@*ked me. The product incompatibility is preventing any adhesion...so I already need to get the metal cut out.

I'm at my wits end...I've had to sand down my work 3 times already. There is nothing more I can do, but get it all cut out and replaced...cars not worth that economically speaking.

Going in to have a cold snack.

 

@SyntheticAtmosphere, is there a way to spray oil in between the outer quarter panel and inner panel inside the wheel housing without drilling a hole?

It sounds like you're very experienced with this kind of work.

With the way this has gone for me, I can't say I'll ever try it again. There's a shop that does minor paint touch ups that I'll take all future cars to.

And going forward, all of my cars will be treated with KROWN annually.

 

If you remove the plastic panels inside the trunk area, you can usually see the back of the quarter panel and wheel well. Sometimes the fuel filler housing makes it difficult if you are working on that side.

Krown is a great product. I have seen a few minty usually not so classic rides through the local known shop.

Good luck.

Sent from my SM-G930W8 using Tapatalk

 

Well, I finished the paint repairs as best I could. What should have taken me a couple days turned into 8 days of frustration. I'm really not too sure how the repairs will hold up.

So, I spoke to another autobody supply shop that was incredibly helpful and we confirmed the following:

1) It would have been the Krown treatment oil that was weeping through the seam, which is good. It is supposed to slow corrosion down, not sure to what extent.
2) It was this oil that was chasing the primers and POR-15 away from the seam. In the future, I would grind to bare metal, degrease, acid etch the metal, apply a small amount of seam sealer to prevent the migration of the Krown oil. Remove excess seam sealer, let cure, degrease again, apply POR-15 over affected areas.
3) I would apply seam sealer, then prime, then apply base and clear.

@SyntheticAtmosphere, I'm not sure if I read your post correctly, but are you saying you sandblasted the metal inside of the panels? I've never taken apart my trunk area, but is there really that much room to do so?

Also curious how you control the mess.

 

Yes, from the inside you can sandblast the wheel well to quarter panel seam from the top down to the back of the wheel well easily. The front section/dog leg is harder to reach. Hatch and wagon cars gets a bit harder tho because of the strut towers. All you can do is get as much as you can. The outcome is based on abilities and how bad the problem is. It's always best to get on body issues immediately. The DOM16 will actually bridge pinholes (probably so does POR15) and formed a hard shell that you could wrap over. These tactics are not a restoration but more of a mitigation. Luckily you had Krown, or the issue would have been worse.
Also, you dont control the mess, you shop vac and air blow the abrasives out as best you can. I've duct taped heater hose to the vac hose or used blower wands to get into smaller spaces. You would be amazed how far sand will travel, lol.

Sent from my SM-G930W8 using Tapatalk

 

@SyntheticAtmosphere, yeah my autobody skills are garbage...I definitely know I didn't miss a calling to that profession and I can 100% understand why they charge what they charge.

Unfortunately I only started the Krown treatment this past year, only after I noticed the start of corrosion. Krown is apparently supposed to be able to slow the rate of corrosion by 60-70%, though who knows the truth about that.

Given that tight area, it would be exceedingly difficult to degrease prior to applying something POR-15. And you are correct, POR-15 can supposedly bridge pinholes.

Please be careful with blasting with sand...silica dust is no bueno.

 

It is too bad we cant have nice things for ever. I've never winter driven my 06 Speed6, but that dosent stop wear, stone chips and potholes, lol. Even tho my 15 year old car is a great place to start a restoration (maybe bottom up in 2025ish, pending a new shop build) I have applied bandaids like wrapping a totally b-fucked hood, it's pretty on the outside. My spider cracked front bumper, nice from far. And an aging "thin from the factory" paint job, quoted $7000 for a full repaint.

Try to patch as best you can and enjoy the hell out of it...take care of the driveline and a clean shell will show up. Many people here have done swaps after enjoying a first one.

Sent from my SM-G930W8 using Tapatalk