Surface rust INSIDE rear seat cross-member

[4uall]

[bluespider262]

I'm glad mine isn't that bad. I mean it still has black paint underneath the coating over the floor for the most part.

Miata may seem easier because they are newer, but IMHO you are just trading one set of problems for another. I think that's true of any vehicle that's older than 5-10 years old.

[AriK]

You'd have less troubles with a Miata because they are better built vehicles, but one thing you have with a Spider that you don't have with a Miata is the vintage factor. Even the early ones from the late 80s are hardly considered vintage (in my eyes anyway). Keep up the good work and proceed with your restoration, you'll get more recognition out of owning the Fiat.

[124JOE]

have you ever looked under a miata"yuk i feel bad just wrighting it"
the tube holding the rear end leaves nowhere to jack it up

[superbenk]

You guys are right, of course - the Fiat definitely has a novel class about it that no Miata has. Can't argue there. I just HATE rust now & it's making me grumpy

I cut another access hole in the top of the crossmember tonight & scraped out as much loose rust as I could. I don't think mine is in dire shape so I'm not going to pull it apart any further. I have a couple pin holes between the trailing arm & the driveshaft tunnel, but nothing right around the trailing arm mount - that looks pretty solid.

I worked the contents of one of the Krud Kutter bottles in the crossmember & spread it around as best as I could. Tomorrow when it's fully dry I'll try to coat the interior as completely as possible with the Rustoleum Rust Reformer spray. When that dries I'll weld patches in the access holes on Saturday & call it good.

Here's the cleaned up pan behind the crossmember where you can see the pin-holes:



Here's inside the crossmember with the Krud Kutter applied:

[SoFlaFiat]

... I shoulda bought a Miata

Haha!!
Watch out!
There are those amougst us who consider them to be fightin words!!!

I get not wanting to dig to deep but there sure is satisfaction in doing the job right and knowing what you have in the end.
Just please spend the time to check the trailing arm mount areas so you can feel safe driving it!

[superbenk]

... I shoulda bought a Miata

Haha!!
Watch out!
There are those amougst us who consider them to be fightin words!!!

I get not wanting to dig to deep but there sure is satisfaction in doing the job right and knowing what you have in the end.
Just please spend the time to check the trailing arm mount areas so you can feel safe driving it!

Haha, right you are. I wanted a project & a project is what I got. My tune will change dramatically the first time I take it out this summer! Last summer was pretty darn fun with this car. Just need to get through this mess & get back on the road again.

I sprayed the driver's side with the first coat of Rustoleum Rust Reformer last night & I think it's turning out pretty good. Tried to get some pics of the inside:

View from the frame rail towards the tunnel:


Another view from the frame rail towards the tunnel:


Close-up of the tunnel from the inside access hole:

[DieselSpider]

Keep at it and you'll get it where it needs to be.

I have co-workers with Miata's who once they ride in the Spider are saying the opposite - "I wish I bought the Fiat Spider". And these are guys who bought a new Miata within the past 2 years. They love the ride, sound and especially the way the turned up visors deflect the wind over your head. You just don't get that childlike ear to ear smile from riding in the Miata.

One co-worker was just blown away by being able to toss his bag into the back seat and not having to stow it in his lap or on the floor in front of the seat.

[bluespider262]

That doesn't look so hot. I bet you can poke a screwdriver right through in many spots along the top and bottom if you pull the control arm mount off the bottom.

The rest of your crossmember looks great though.

[superbenk]

That doesn't look so hot. I bet you can poke a screwdriver right through in many spots along the top and bottom if you pull the control arm mount off the bottom.

The rest of your crossmember looks great though.

Well, you guilted me into going a step further & pulling the passenger side trailing arm off to check under it. The passenger side was worse with rust so I figured it'd be a good place to start. Everything under the mount was solid and completely rust-free! The only rust was at the front edge where I had a hole in the pan that I've already patched with welded in steel. Here's a pic of the spot - note the tan stuff is residue from the flux welding I did early on (doing MIG now). You can also see the scrape marks where I jabbed at the floor with a screwdriver to make sure it was totally solid:



Here you can get a broader view where you can see the patches I welded into the floor, but the part under/inside the cross-member is solid:



Throwing some of the Rustoleum Rust Reformer on there just to be sure & will cover that with undercoating to match (maybe, or just top-coat spray paint).

I was happy to note the Krud Kutter is pretty much the same stuff that ships with the POR15 kit & way cheaper (both are just phosphoric acid). That allows me to be extra liberal with the stuff to make sure any all rust that can be killed will be.

[bluespider262]

Looking good!

This is probably the best thing you can put on that bare metal and its just as easy as Rustoleum. Pricey, but nothing is going to seal those panels as well as 2K primer. There's other companies that make an equivalent product but I don't think you'll find this at a home improvement store or anything like that.

You can then put the undercoat over that for a consistent look if that's important.

http://www.eastwood.com/eastwood-s-2k-a ... -gray.html

[spider124]

I saw this product on the Eastwood site called Internal Frame Coating.
http://www.eastwood.com/internal-frame- ... ozzle.html

[spiderman1]

I am at this exact spot on my 1982. My floor pans are rusted up against the cross member. Can you tell me how you removed the front part? Do you have pictures of that process?

[SoFlaFiat]

I have replied to a couple emails about the process I went through with this and thought it best to copy my last reply here:
Here is what I would do first (and maybe you have already)
Drop the front mounts for the long trailing arms. I'm a little bit insane so I would actually remove the trailing arms and brackets, clean paint etc. but you don't have to. You can leave the mounts attached to the arms and just drop them down away from the unibody.
From the bottom, scrape, wire wheel (any method the works for you) and remove the undercoating and paint anywhere that looks questionable. If the whole rear floor is a mess, then I would cut the cross member like I did. If you have a couple small areas, I would drill out the spot welds where the cross member is attached to the floor panel (only where you need to remove a section of floor) and then cut that bit of floor and replace. If you have rust as extensive as mine, you may want to dig as deep as I did. Obviously there are different methods and approaches. I found it easier to remove the front half and not the whole thing. You will have to drill out about 100 spot welds and simply cut along the top. There are reinforcing plates on the inside, front of the cross member, at the trailing arm mounts that will need to be removed separately.
I cleaned and coated the whole area, using weld through primer where needed. Replaced the floor sections as needed and welded it all back together.
If you take a look at my blog (link in my signature line) I am pretty sure it was around April 2014 that I was in the middle of this (wow! 2 years already!!)
You can search by month in the sidebar on the right.
I posted some pictures there but can probably dig up more. I hope this helps and please don't hesitate to ask further.
Best of luck!

[superbenk]

SoFlaFiat, I'm SUPER-impressed! Loving looking through the pictures you have. You are WAAAAY deeper into your project than I am. I wish I had the time, money, motivation to get that involved in mine but for now it'll just be a driver for fun. Maybe someday I'll tackle a full-on restore/mod like yours. Really inspiring stuff, thanks for sharing!