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Posted by: jsteele22 Nov 26 2006, 06:38 PM

So I've been working on my RH hell hole area as time, weather, and motivation allow. Using a wire wheel wasn't cutting it, so I got some blue (AlO2) gringing wheels for the electric drill. In the affected areas, I seem to cut through (in order) : colored paint, black layer, powdery rust, shiny metal.

Q1) The black layer is very tough, and doesn't seem to appear in areas where no rust occurred. Could this be some PO's rust converter job ? There is definitly some rust under the black stuff.

The rust situation is not bad in general. Apart from the battery tray, which I removed, there are no rusted through areas. But I've been a little worried about how strong the remaining metal is after pitting due to rust and then my grinding. Then, down in the very worst part of hell, not far from the "drain" hole, I found a tiny (1/16") spot that looked like a hole. I went at it pretty agressively with a blunt grinding wheel and found this :



My first thought was that the rust had started to penetrate outwards from a deep pit and form a large flake. So I went at it with a screwdriver, and started prying up the top layer. Here's what I found. (Although the rust-colored dust really stands out in the flash picture, in real life everything looks quite a bit cleaner.) :



And here's where it's located :


In the close-up, you can see smooth, grey primer surfaces between the two layers. In real life, the bottom layer looks clean and rust free (apart from the rust powder.)

Q2) What is going on here ? Are there really supposed to be two layers of metal ? How far does the 2-layer portion extend ? ( It doesn't look like a repair job to me, but ya never know...)

Q3) Although there aren't any more rusted-through holes, the metal in the deeply pitted zone is pretty flimsy, or at least it will be when I grind the rust off (like the part I pulled up with a screwdriver). What should I do : small patch just to seal the hole ? Cut out "top" layer of pitted metal and replace it ? Leave pitted layer in place and patch over it ? Bondo and sell to Ferg ?

Posted by: jsteele22 Nov 26 2006, 06:55 PM

Oh, I meant to ask : is that surface that has the hole in it part of the "long" ? I'm still learning my way around the chassis...

Posted by: majkos Nov 26 2006, 07:01 PM

I don't know what you're bitching about, That's one of the nicest Hell hole I seen in a long time!

I'm not sure on what to do next, but I * think* POR 15 should suffice.

BTW, Ferg is a little more pickier, he likes it all the same color as the car,
you shouldn't have "sanded" that area

Posted by: Vacca Rabite Nov 26 2006, 07:27 PM

Dude you have NOTHING to worry about here.

The long is the the metal framework that runs from thefront of the rear fenders to the rear of the front fenders. Your Hell Hole is part of the long, the part that is most likely to rust out.

Also pull your rocker panels off and look close around the jack points. But looking at your hole, you probably have nothering at all to worry about. Clear off the surface rust, POR-15 the hell out of it and you will be in good shape.

This is a rusted hell hole (and not even badly rusted, at that):

I would have killed to have yours.

Zach

Posted by: highways Nov 26 2006, 09:48 PM

Nice hell hole! That's what people call a 'rust free' car

You just have widespread surface rust but it obviously hasn't even compromised the first layer of sheetmetal on the top of the long there since you can see clean metal underneath where you went digging. I would remove the surface rust (I like to use a grinder with a wire wheel, goes really fast). Some guys say it goes too fast and heats up the metal which comprimises it. Whatever. I think if you just do it somewhat gently and don't heat things up it would be okay. Then I would spray it with a self etching primer. ZeroRust has an etching component and it's been tested side by side with POR-15 on dock piling subjected to tidal movement and saltwater. ZeroRust won the test after 1 year.

If you want to get crazy about it you could use some PPG metal cleaner, then PPG metal etch, then the Zero Rust or other primer. If you want to read alot of great bodywork info look here:
http://www.autobody101.com/forums/

But you definitely don't need to cut anything... just clean, and get some good paint on there to preserve what you've got.

Posted by: sww914 Nov 26 2006, 10:26 PM

Some guys say it goes too fast and heats up the metal which comprimises it. Whatever.


So, they think the metal didn't get hot when it was welded together?
Whatever is right.

Posted by: jsteele22 Nov 27 2006, 10:45 AM

So as long as the second layer of metal doesn't have any rust, I'm okay structurally ? The top layer only has that one hole in it, but overall a lot of material has been removed by rust and by grinding.

Posted by: gopack Nov 27 2006, 11:26 AM

here is a pic of an opened up hell hole
If I am not mistaken, that is the LONG under the sheet metal of the hell hole area.



that unit is much heavier guage and seems to be the structural part of the long


lots more pics of that area at photobucket.com, search for gopack42 to see the pics

Posted by: highways Nov 27 2006, 12:57 PM

Dude.. it only has that whole because you made that hole! No but it's fine, you just went exploring and had to convince youself. The long is a box and I think there are two layers of metal there. You poked through some thinner sheetmetal on the top- not so structural. The next layer is a little thicker. Ultimately you will want to seal that exploring hole back up so that no water can ever work it's way in there. For that I would spray the Zerorust paint in there wet so it runs in as much as possible sealing up the edges. Then you might want to throw a good quality bondo patch to plug it even further.

You've got plenty of metal everywhere. You're structure is not compromised in the least even if there were a few small holes. You just want to preserve it for the future even if it's slightly thinner from gentle wirebrushing (you should not be grinding- you're metal is too good so don't grind it away) The goal is to not have any intrusions which will allow water to enter the inside of the long and begin the rusting from the inside out.

When you go exploring with a screwdriver... bad rusted areas should flake off with ease- as if it was a rotten log of wood. If it is a bit tougher- like a healthy log of wood you don't need to worry or force anything. You are only looking for crumbling swiss cheese- which is usually evident by holes that are already present. If it doesn't crumble or look like it would let water in- then you have been blessed by the 914 gods.

Posted by: jsteele22 Nov 27 2006, 02:41 PM

Okay, okay. I'll find sumpn else to worry about