How the heck do I fix this? (Rust under windshield)

[macdude443]

I figure the glass has to be pulled before I can really look at it.  Can this piece be cut out of a donor car and welded in easily?  I've never seen the part from under the glass, so I'm not sure if it connects to the dash or not.  I can't yet tell how deep the rust is.  Has anyone else repaired heavy rust here?

[shaggimo]

You will have to pull the windshield to better assess the damage done. Eaglegirls' SX/4 had the same issue. After removing the windshield, I sandblasted the whole pocket, that exposed a few pin holes. I know my fix isn't the correct way, but, I didn't have access to a parts car with a good cowl. So I mixed up some fiberglass reinforced body filler and gave it a skim coat in the bad areas. It was only pin holes, so not a huge deal, if you have severe rot, best bet would be to either cut a cowl out of another car, or if you are a decent fabricator, make patch pieces. Either way you go, It's no fun, Cutting out the cowl is a project, making patches, would likely be easier. On a side note, so far my repair has held up perfectly fine, though I took extra care to douse the underside of the cowl (accessed through the wiper motor hole) with paint, however her car does not see winter, so take that into consideration.

[priya]

When you get the windshield out so you can see where the windshield lays against the cowl you'll see there is a lip at a right angle to the flange the lower windshield lays against.  There's holes in this lip that the dash screws to.


  Whether you're better to patch or replace the piece from a doner car will depend on the extent of the rust.  As shaggimo said you'll need to sandblast the area first and remove the front fenders to assess the rust that the fender is covering.  If you just have a few pinholes that you can fix with a 2 or 3 inch patch that will be the better way to go.  If there is pinholing along most of the length of the lower windshield channel you'll be better off to cut this piece from a doner car and weld in as the lower channel is a compound curve and anything longer than a 2 or 3 inch patch is going to be difficult or impossible to form to an acceptable level with hand tools.  As well, the lower lip needs to be precisely positioned and if you're trying to handform longer patches your odds of getting your patch close enough to the necessary position are slim to none.

It may not be as bad as it looks, I thought I was going to have problems in my windshield area as well:


After sandlbasting you can see the rust had some effect but it wasn't deep enough that repairs were needed.  Check after sandblasting to see if you need to repair the area by taking a pointy object like a scratch awl and see if you can push it through the pitted area.  If it goes through you need new metal, if not you're okay to fill and paint.  Like Shaggimo I like to use a short strand fiberglass filler to cover the pits first, then sand, prime, and paint.  If you have only a few sparse pinholes and the rest of the panel looks solid you may be able to get away with spot welding them shut with a MIG.  If I remember correctly I had two pinholes in the windshield pillar shown and I gave them a quick zap with the mig to fill them.


If you do decide its better to replace the panel with a piece from a donor vehicle I suggest making the cut inside the engine compartment rather than along the exposed area where the vent holes are.  That way  you don't have a whole pile of work to do to make it look smooth.  Once you get the fenders off, all the spot welds are accessible for that entire panel so you could remove your old piece at the factory spot welds and put in the doner piece in the same way the factory did.  It'd might be more work, but would be a nicer job.

[macdude443]

Thanks for the advice and pictures.  I'll just have to see where to do all this.  I don't feel extremely confident taking out the glass myself, but I've never done it before.  It won't be ready to drive until Spring, so I can't take it anywhere to pull the glass.  I imagine it would cost a lot more to have someone come out and take it out.  Any input on glass removal, or a thread that covers it well?

[rohnk]

If you find a company that will do windshield installs at your house, they often times will have a service to remove windshields as well. Usually a small fee like $30 or something to do it for you.

[priya]

I didn't want to remove the glass myself so I had a glass installer come out and remove it.  If I remember correctly it was $50.  I have removed windshields before.  I used two wooden dowls with piano wire wrapped around them.  First remove the windshield trim, be careful not to leaver a screwdriver or some such against the windshield to pop it loose or you'll likely crack the windshield.  I leavered a screwdriver against my hand resting on the windshield, pretty painful, but it works, or if you're strung enough you can get a flat piece of metal under the trim and pull away without touching the glass.  Then remove all the clips, some of them will likely be glued in with urethane so you'll have to dig  them out with a utility knife.  Then take your piano wire and push it through the urethane between the window and the metal windshield channel.    Wrap the wire around the dowels and then with one person inside and one outside pull the dowels back and forth in a sawing motion and gradually pull the wire along the lenght of the channel until you've cut all the way through the entire circumference of the window.  It's tough to get around the corners you just have to keep sawing and keep pulling in the direction you want to go and it'll eventually pull around them.  Then have a couple of people outside the car to grab the windshield and the person on the inside can push it outwards and the other two can grab it and put it in a safe place.  Some auto stores sell steel dowls for this job that have a hole through which you can route the piano wire, those work well to.

[macdude443]

If it's that cheap I may just have someone come do it.  I thought it was about $100.

[macdude443]

I pulled the windshield.  The sides and top are fine.  The metal on the bottom is rough but solid.  There are a few pinholes, so we filled them with the MIG.  Oddly enough, the holes are on the top edge of the channel, inside the car.  There were no holes on the bottom part of the channel.

I made a trip to eastwood and bought rust converter and red rust encapsulator.  I didn't want to risk weakening the metal by blasting it or grinding at it.  I'm currently waiting a few days for the converter to cure.  I'll then put on the encapsulator, followed by epoxy primer and a high-build primer.  The sides/top still has some of the old urethane on it, so I'm only going to prime the exposed areas.