I have been a member here for awhile, but have not posted in a few years.

I have an 1979 L48/auto car I bought in 2013, and stored outside and used as my daily driver in the salt of northern Utah until 2017. The previous owner drove the car the same way for an unknown period of time. I am finally pulled the motor last weekend and I am getting started on what I hope will be an easy restoration, but I need some advice. When I bought the car I believed it to be pretty rust free. Below are some pics of the #2 body mount area and windshield header on the driver side, which both seem pretty solid to me. However the car leaks badly in the rain, and the drivers side floor pan fills with water from behind the kick panels. I have tried using a vacuum to clean any debris that may have fallen into the drain path, but nothing comes out.

I am concerned that there is major rust in the birdcage at the base of the windshield frame that is causing a leak path, but I do not know how to inspect that area with the front clip installed. These are pics of my car





And this is what I dont want to find (NOT my car). Any pro tips on how to inspect this area with the front clip and windshield in place? I am nervous because this car looks as clean as mine does around most of the windshield frame, but the bottom corner is completely gone...

 

Looks like the dash is still installed which will make it hard to look at the inside of the screen surround which can help with a diagnosis of the area.

Also the area with the door(s) open can help as well.

Taking the stainless trim off the top of the screen will tell you a lot.

Take the access covers off the #3 mounts while your doing all that as well.

I have seen badly rusted cars only on one side with the other in good condition as well.
Post more pictures here , people that have actually resurrected rusty old cars will chime in with their experienced knowledge.

 

id have to see more pics, but that doesnt look that bad. check mount number 3, remove access cover in rear wheel well, pull t top staineless, take a look when the door is open above the upper door hinges, there is 2 pieces of metal and a lip, good indicator of rust under fender. pull sill plates and check rocker rail plug hole areas. its all fixable just depends on how much time you want to put into it, i just did both rocker rails, #3 reinforments, lower outer windsheild corners, upper windsheild corners and a few other repairs,

 

I pulled off the windshield trim this morning, and it looks about how I remembered. There is a bit more surface rust than 5 years ago, but still no blisters or holes/flaking sections. I tried to take some pictures inside the the door areas, but it was very challenging due to glare off the body. There is some poorly applied and painted-over adhesive on the metal piece above the top hinge, but I picked some of it off and there does not seem to be a serious rust problem there either. See the last couple pics showing this area.

However, the fenders on both sides appear to have been bonded at this area but are currently broken away. I am not sure how that is possible, but there is a large gap on the passenger side. All the door and fender gaps are still fine (for a 70s GM car), so I am not sure how there can be a huge gap between the fender and where it appears to have been bonded previously. I guess I dont really care that much unless this indicates some other problem, because this area is hidden with the doors closed...

Also is there a better way to attach images on this forum? I thought we used to have them behave like regular attachments, instead of appearing in line with text. Sorry if so many pictures in line makes this hard to scroll through.























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If I was restoring that car, I don't see anything in the pictures you've posted I'd feel a need to make rust repairs on. These cars often leak due to failed glue/caulk joints even when the car does not have significant rust. Sounds like the car may have been in an accident and the joints where the fenders were glued on have been broken free. Do all the doors and glass line up nicely?

 

The doors are pretty good, except one spot toward the front top area where the fender and door are a different shape. They close easily with 2 fingers. The glass alignment is also pretty good.

I know the T Tops leak a bit at the rear, and water drips down the rear area into the battery box. However, I believe the leaking at the front into the foot wells is different and unrelated to the T top leaks (could be wrong about that though?). If that joint is already broken, does that make it at all easier to remove the front clip (which would let me fully inspect the area I am concerned might have rust damage)? In order to re-bond the fenders and replace any bad caulking, it seems like the fenders wound need to be removed to get access and bond prep the area.

 

You say water fills the driver side floor when it rains. So you have a good leak. Keep digging deeper til you find it. I'd pull the windshield side trim, the top dash pad, and the windshield next.There is a spot above the driver's hinge that does not look healthy.

To get a pretty good look at the top side of that section you'll need to pull the windshield. And that gasket alone could be your problem as well, my windshield gasket was completely un-attached to the frame except for a 12 inch section.
Oh- check under the carpets too, don't 79's have metal floorboards?

 

Where are you getting water? In the floors?
I would be willing to bet that your side wells are leaking on the kick panels. - The plenum where the wipers are directs air down the sides of the cowl into the area behind where your door hinges are which can then be ducted into the footwells, the kick panels require a bedding compound which is about 1" diameter snake for lack of better description - of waterproof non hardening putty - if you don't use it they will leak and you will chase it for ever... ALSO the top molding for the T'tops must be sealed as shown in the second photo... if not what happens is water drives behind the windshield molding into the trough and then over the pinchweld into the back then drips inside... and you will think it's your T-top seals... IT'S NOT!

 

Also put a daub of sealer on the top of all of the brackets which you screw the chrome recess phillips screws into.

 

You must wipe sealer into the leading edge of the chrome trim - then when you press it down over the lip behind the windshield and screw it down you have a water tight seal...
ALSO where ever there is an overlapping joint between the T-top trim.
Water will find a way in ESPECIALLY WHEN DRIVING.

You cannot use too much on the kick panels,
I use plumbers putty which is non hardening and is waterproof.

 

Based on the other pictures provided and my own expience, I think its likely this is all loose old caulking and once removed there will be no rust problem requiring repairs. Of course you never know for sure until you dig it out. I use an old flat tip screwdriver and a light hammer to chisel out old caulk like this that has been heavily applied. I keep one old flat tip screwdriver just for bodywork. If you do the same you want a screwdriver without sharp corners or edge, a flat tip screw driver no longer great for driving screws due to wear is what I recommend.

 

Thanks everyone for your feedback so far. I had today off work, and cut out the caulk over the drivers side door hinge. Also took some photos of the floor. There is a little bit of blistering rust in the doorjamb about at the bottom of the windshield, but there is still mostly good solid metal underneath.

The visible ares of the birdcage, the floors and frame all seem pretty solid. Most of the gray paint on the birdcage is gone or flaking away, however. Would you recommend somehow trying to prep and paint the accessible areas of the birdcage, or is this a waste of time if I don't strip the entire car down so I can paint the whole birdcage instead of just visible portions of it?

There is also some thick rubber sealer of some type all over the floors (see last 2 pics) that I have never seen on other GM vehicles. Is this stuff original? If so, what is it? Its flaking away and has incomplete coverage in some areas, so I would like to either repair it or strip and paint the floors depending on what is more correct.


























I had no idea about the rubber putty stuff, and I need to get some. None of my T top trim has any sealant (stainless pieces are just laid on top of each other, allowing leaks...), but I don't understand where it would be used on the kick panels. When I think of "kick panels" I am thinking of the flat plastic piece that covers the body mount at the front of the cab, and mine definitely don't have a door on them like in your photo. I'll have to dig out my AIM, but my kick panels dont look anything like that and I am not sure how they would seal at all. I believe water is getting into the body mount area and flooding over into the floors, and I am not sure how I could get the kick panels to stop that.

 

This crusty area is the only place of concern I see. Take an ice pick or sheet metal scribe and see if you can poke it through the crusty area. If not, just clean off the crusties and you should be good to go. If the scribe goes through some rust repairs there would be advised. It appears there are also some crusties in that picture under the paint you have not yet removed. As for the stuff on the floor, I speculate that a previous owner applied it to cover up rust pin-holing. If it were my car, I'd paint/preserve the areas of the bird cage you can get too, even if you're not doing it all because its too hard to get at.

 

No idea if it's original, but my '78 appears to have the same sealer on the floor as yours.

 

Rust is the only accessory you get for free with a C3
bfit