Originally Posted by jbtvt

I've fixed this issue on multiple vehicles without recurrence, for up to four years and counting at this point. First pull all the trim around the entire windshield, then scrape all loose rust using a screwdriver and run a rough sandpaper thoroughly over it. If you need to paint any areas make sure they're extra clean. Blow out the joint and treat with phosphoric acid per directions on bottle (or as a second choice, any phosphoric acid containing primer).

If you can't cover the entire affected area with caulking and need to paint, follow acid treatment with primer and paint. Let dry and then masking tape both sides of the joint all the way around the windshield and fill with Dow Corning 795 silicone sealant. This is not your typical hardware store caulk, it is professional glaziers sealant and makes all the difference - does not shrink or oxidize at all and has unsurpassed adhesion and flexibility. It's sold by industrial supply stores, or online at Amazon, not cheap, but worth it unless you want to do this every year. Finally, tool the joint with a plastic putty knife, and throw away that worthless, water-holding trim.

My windshield, before cleaning up the joints after it dries -

Originally Posted by bootown

yeah, i had to have that fixed in my last 4runner. i talked to a guy installing my windshield one time and he told me it was because of how most installers remove the windshield. i can't remember how he did it, but i commented on how i liked how he was removing mine which then led to our conversation of installers as the cause for rust starting there. they roll on some black stuff after they hack up your paint to "prevent rust" from starting but it doesn't work

Originally Posted by jbtvt

Yeah

Originally Posted by RPS99SHO

How did you fix it?

Originally Posted by RPS99SHO

Ever seen this before?

Originally Posted by Scramble

I hope mine doesn't look like this when I pull the glass.

Originally Posted by Mark_BC

... I just don't know how this would work if I am doing the repair work on the paint. Maybe I can remove it myself, repair it, then do a temporary jerry rig job to re-install the bad windshield with a few silicone dabs here and there so I can drive it into the shop for them to put the new windshield in.

Originally Posted by Mark_BC

I don't trust an auto glass shop to do this, they are probably the ones who caused the problem in the first place by scratching the paint. I am sure the rust on my mom's is from shoddy windshield removal and not repairing the scratches properly. The windshield is cracked so it will be covered by insurance (minus deductible), I just don't know how this would work if I am doing the repair work on the paint. Maybe I can remove it myself, repair it, then do a temporary jerry rig job to re-install the bad windshield with a few silicone dabs here and there so I can drive it into the shop for them to put the new windshield in.

Originally Posted by k2damfc

Mine looks just as bad. I went to a body shop and they told me I would have to have them cut a whole front section of a roof off one and weld it into mine. Around $3000 to do it. Nope!

So what I have done, and currently in the process of doing:

1. Friend came over and welded the big holes, which was hard due to how thin it is

2. Used metallic bondo to fill any deep/big holes. Sanded and need another coat

3. My next steps: POR15 the inside of the frame and outside over rust spots

4. Resand all around and primer then paint



I don’t know body work at all so first mission on this kinda stuff. I feel it would be easier to rhino line all around the windshield so I don’t have to worry about keeping the rust areas super smooth, but not sure how I would blend it with existing paint. Currently I sanded down 4” above windshield and dont mind having 2 tone look on the front.

Also the POR15 rust sealant I got says prep with metal etching solution but they don’t sell that at same place. Can I just sand it down? Can I put POR15 over bondo?