Rust Dilema

[Feadz]

Well it seems that my effort of locating and driving 7 hours away for a rust free 240 was pointless.

Background: This is just my project car, not a daily.I bought it last summer, it was rustless and clean! I'm not sure if anyone followed my turbo set up thread in the ka-t section, but I have my whole turbo set up complete and ready to install this winter. I'm actually in the process of installing my clutch and that's when I found these two problem areas...

A few days ago I had my hatch on a lift and noticed that my drivers rail had a small hole starting to appear, so I started poking at it and it resulted in this: (pictures of when i first bought it, and now)


I can't express how extremely mad/paranoid I was at that point, so I spent about an hour going around the whole under body of the car and pushing to see if there were any weak spots and then this happened: ( now, and when I first bought it)

This spot isn't as big as it looks, it's the spot that I circled in red on the right, located under the rear seat area.

As you can see from the pictures the under body was rustless last summer when I bought it, but somehow rust seemed to find its way to me even though it was garaged during the winter. The rest of my car is fine from what I can see, all of the other common rust spots( strut towers, rocker panels, wheel wells, etc...) are spotless, so i'm not giving up.

Here's my plan.. first off I'm going to strip the interior and remove all of the sound deadening via the dry ice method and hopefully not find any more rust. Once stripped, I'm going to cut out the section in the floor pan where the rust is eating through and weld in a plate. After all that is taken care of I am going to either use POR-15 or rustbullet to coat the entire floorpan then reinstall the carpet and interior. For the frame rail, I was planning on cutting out the rusted area then making a channel section to weld over that spot, similar to the xcessive weld in frame section.

Does this sound like a decent plan? Should I buy enough POR-15/Rust bullet to do the whole underside of the car too? Finally, does anyone have an experience with either POR or rust bullet that could offer some opinions?

Also, given my situation of going from rustless to rust in under a year without driving it in any salty/snowy conditions, I really don't plan on buying a new 240 in fear of it happening again and rather try to redeem my 240 and defeat the cancer we call rust.

[konjiki7]

Sounds good I'm going to be doing the something soon. I'm going to be using bed liner inside and under the car. (manly for its strength and dampening properties.) Eastwood also has an internal frame rust proofing/killer. I works pretty good used on my friends 87 celica.

BTW I've personally used rust bullet it didn't last very long...1.5 years even though the surface prepping and cleaned before i used it.

[sabretooth91]

Yes, let me know how this goes. I plan on doing something similar, and I don't have any experience with these methods. I've just used fiberglass and body filler. On my daily driver, I had this warranty for rust protection (I forget what it is called). But I had to bring my car in every year to get it re-applied. I forgot once (lived in FL) and now the warranty is void I just moved back to NY, lol. Anyway, I'm not surprised that it only lasted for 1.5 years...

[Feadz]

Good news.

I only found one small rust pin hole in addition to the big ol one in the back seat. I'm only fighting the sticky residue now.





Bad news. Por-15 directions say to only apply it in 50+ degree climate conditions. I'm not sure I can heat my garage up to that temperature.

I've also been reading up some alternatives to por-15 and came across epoxy primer. Does anyone have any experience using epoxy primer?

[liquid_cool]

what you can use is a sealer primer..its apoxi based..or just a plain sealer..this will create a water tight seal between the metal and any other coating you use...alot of guys use rhino liner after the sealer...as for the rust (Cancer)..its not uncommon for 240's to have some type of rust...they were made in a humid climate as fast as they could be produced...water vapor may have been cought in between the layers of paint and primer...over time..this will rust out...hope this helps ya..good luck

[Feadz]

Well just finished this up yesterday... finally. I went with the semi-gloss POR-15 and I it came out pretty nice. Here are some action shots...


I followed the proper procedures which included sanding all the paint off to bare metal.


I cleaned/degreased the floor with POR-15's marine clean.

Once that was dry I used POR-15's Metal ready to etch and coat the floor with a zinc phosphate coating. This made the smooth sanded surface very rough.


Rinsed with water and let it dry and taped up all the valleys of the floorpan to get ready for the POR-15.



I did two coats, the first coat was about a millimeter thick, followed by a thicker second coat once the first became tacky.



It didn't take much to paint, in total I only used about 3 4oz cans of the stuff. Time to bolt everything back together.

[Feadz]

Finished it up today, fitted in the new black carpet from stockinteriors. The install wasn't as bad as everyone makes it out to be, but here are some fitment shots.

Old nasty..


Test fit #1


Trimmed and fitted:


A lot of thanks to the dash removal guide and vert carpet install in the tech pages.