Rusted windshield repair using POR15 and Kittyhair: Procedure and results

dmwaves

New member
Here is how I repaired the rust and the holes around my windshield - very pleased with the results. Hope this helps someone. Shout out for POR15.

VAN: 2004 Sprinter, 110K, near ocean, mlld climate but faulty windshield replacements in past with scratching of metal leading to rust. Rust repaired once by bodyshop- no joy. Rust never sleeps. When the windshield was removed- we saw that it was replaced over rust- bad!!

Windshield due for replacement- time to address (too long) neglected rust.

TOOLS- drill with 3m fiber wheel to remove rust/pant: http://www.amazon.com/3M-Paint-Rust...8278837&sr=8-1&keywords=3m+rust+removal+wheel ,

pneumatic needle descaler (optional, but makes the job go fast): http://www.northerntool.com/shop/to..._sku=1585560&gclid=CLWrmK3AycsCFdgMgQodF9IALg

POR15 starter kit (essential IMHO): http://www.amazon.com/POR-15-45009-...&qid=1458279056&sr=8-1&keywords=POR15+starter

Kittyhair body filler (to fill couple of dime sized holes that were rusted through- essential): http://www.amazon.com/POR-15-45009-...&qid=1458279056&sr=8-1&keywords=POR15+starter

Regular body filler for final: http://www.amazon.com/Evercoat-406-...srs=2591500011&ie=UTF8&qid=1458281297&sr=1-31

JB Weld plastic filler: very useful: http://www.amazon.com/J-B-Weld-5013...458280334&sr=8-1&keywords=jb+weld+plasticweld

Sandpaper 80 grit and 320 grit

bed-liner paint (to paint area above and below windshield- optional):any brand, alternatively color matched paint for your van

folding ladder

friend to help (optional)

COST- windshield through GEICO/Safelite $100 deductible, above costs, one weekend, 1-2 six-pack job.

PROCEDURE: 1) Suggest window removal first (we removed the moulding and did the area outside the window first b/c we were newbies; would now recommend do entire procedure outside and under window at one time after window removal). We removed the hood to get better access and allow standing on radiator support when working on the top windshield area. Remove the wipers.

2) cover dash and van seats with a drop cloth, pull back and tape off A pillar covers

3) use needle scaler and go around the windshield channel and surrounding area. Remove all rust- do not worry about punching through weak rusted metal- this is bad metal and you want it otta there. Can alternatively use 3m wheel for this purpose. Don't be afraid.

4) use 3m wheel and remove all gasket material, paint and other residue from the window channel. Try to get shiny metal surface all around window channel and any areas where there is rust damage outside of the window channel. The rusted areas will go down to silver/grey- try to get most of the black off. POR15 will work over rust, all rust does not need to be removed, but you for sure want to get the thick rusted scale off. Wire brush and blow out/vacuum/wipe out grit that remains. This step is the most important- you want to get all of the crap out, and get down to bare metal. Any rust and any bubbles in the surrounding paint need to be taken down. It is OK if there are holes- we will fix those.

5) Use the three step POR15 process- use the included degreaser/cleaner (although I am told that simple green will work). Use the included metal prep liberally- it is a phosphoric acid and ?zinc solution that neutralizes rust- I think it converts it to ferric phosphate. Let it soak in and keep wet for 20 min or so. Wash off with water or a wet rag. Apply the POR15 coating over all of the areas. I applied it over the entire area above and below my windshield as well- the rusted pitting as well as the surrounding area. Once the initial POR15 coat is on- recoat 2 more times after tacky. The stuff flows really well and the little can goes a long way. After 3 coats the surface will be a shiny hard black porcelain like surface- when you try to sand it, even with a power sander, you will see how tough it is. You have now created a very very hard surface that is bonded to the underlying damaged metal as well as the undamaged metal. It is impervious to moisture- preventing future rust.

6) Repair the holes. I had a couple of dime sized holes that were left once the rust was removed. I had painted these with POR15 coating and used a Q-tip to get inside and under the rusted area on the back of the metal.

Repair the holes with the Kitty hair body filler. Don't use regular Bondo. The Kitty hair has fiberglass strands that give structural strength. Mix the Kittyhair with the hardening cream, then smooth on with a spreading blade. After the Kitty hair dries, sand it down to nearly flush- it is pretty strong. We used 80 grit sand paper followed by 320 grit. We followed with regular body filler- but this is not really necessary.

7) Finish up the body repair- when we were done, we had a couple of holes the size of pin-heads- these can be fixed with more kitty hair.

8) Repaint all of the body repaired areas with a couple more coats of POR15. Now you have taken the crappy rusted metal down to good metal, covered and sealed with the POR15 treatment, fixed the holes with fiberglass reinforced filler, and now recovered with the very hard POR15. You are left with a strong structurally sound surface, the rust is gone , and the surface is smooth and protected. It will be dimpled and irregular b/c of the pitting, but that is OK b/c it is still protected. Most of that area will be under the new windshield and not visible.

JBWeld Plastic weld- We had a couple of pinhole areas where we were concerned that the fiberglass kitty hair covered by POR15 was thin and potentially weak - we covered these with a coating of JB weld plastic filler- greatstuff! Squirt out of the double syringe, mix, apply with a spreader. Flows very smoothly , fills in gaps, adheres to the smooth POR15 surface , sets up in an hour and is sand-able. Very strong stuff! This comes in a YELLOW double syringe- it was recommended by the customer support representative at JB weld when I called and explained that I was concerned that regular JB weld might not adhere to the smooth POR15 surface. The (US) rep knew exactly what I was talking about and recommended exactly the right product

9) Replace the windshield. We had the glass shop remove the windshield on one day and come back and install the new windshield a couple of days later. They did that, no problem, no extra charge.

10) Cosmetic finish up. We painted the area above the windshield (4 inches up to my Sprinter Westfailia fiberglass roof) as well as the area the area below the windshild where the wipers are located with POR15 (previous steps) and we now covered with black bedliner- matches the windshield surround, covers the surface irregularities. Or you could do a body shop type job with more bondo, body putty, sanding priming, painting color and then clear. We were not into that much work so we used bedliner. POR15 is UV sensitive and needs to be top coated.

OVERALL RESULT: rust gone, source of rust in windshield channel removed and metal protected on a permanent type basis, windshied replaced, cosmetically looks good. Rust should never (never say never...) recur. Very happy with result.

LAST TIP- If your Sprinter windshield is going to be replaced- I recommend POR15 at that time, even if the windshield channel seems good. It would be so easy to do at that stage. I know that sounds like an extreme recommendation, but the POR 15 is as good a prophylactic as you can get. I felt badly that I waited until the rusted areas were over areas that became holes when it was cleaned up- I wish that I would have done this a couple of years ago. (Frankly, I was scared that I couldn't do it, that a body shop would do a crappy job again and F-- it up, or that a good body shop would charge a couple of grand or more...) Now I know that I can do it. If you are sitting on the fence with either a rusty windshield surround or a glass shop that tells you that there is rust under your windshield at the time of glass replacement, I recommend going for it!

Oh, and I am not a shill for POR15, just very happy with the result. Suggest read the Amazon reviews about the product. Good luck!!

Doug
 

Chris9900

Member
This is great timing. I was just at a body shop a few days ago to get a price on this exact problem (rust around my windshield due to crappy replacement of glass for previous owner). He recommended a similar process using Por-15. He has used it for restoration work with fiberglass mesh in bad areas. He didn't mention the kitty hair filler, though. Someone had told me previously that normal filler is not adequate for repairs at the windshield as it's not structural enough, so this sounds like a good solution. I think I'll give it a try as soon as I finish putting my new front brake pads and rotors on!
 

dmwaves

New member
Good luck, Chris! My friend who helped had a good line: "No one else cares about your van as much as you do." In other words, taking the job to someone else can take you down the road of uncraftsman-like work. That is what happened with my first repair at the body shop.

Oh, one other tip. POR15 is water soluble- it you drip on an area by accident, it will come off if you wipe it up right away with a wet rag, but it has to be within the first couple of minutes. Before I learned this, i got a few drips outside my work area. Gonna take some real work to get them off now. Learning curves are a bitch....

Doug
 

Chris9900

Member
Brakes and rotors are done, no lights on the dash and it stops great! :cheers:

I have the windshield removal scheduled for Monday, and am rounding up the supplies between now and then. I bought an air needle scaler last week. My rust is not very bad yet, worse at the bottom edge. I'm wondering if the starter kit is enough of the Por 15?
 

windseye

Member
I followed the procedure in this excellent post through step 5 and am very happy with the results. After finishing with the POR-15 I had Safelite put in the new windshield. I was concerned whether the POR-15 would bond with the windshield adhesive that they use. The tech first applied Sika Aktivator followed by Sika primer. I am no expert but these are both urethane products like POR-15 and although I have no background in the chemistry, I believe that this is similar to the bonding agent that POR-15 makes and recommends. The aktivator seemed to convert the slick POR-15 surface to a much rougher surface and I am confident that the bond will be very strong. Thanks for the how-to.
 

quillaja

2004 2500 140WB high roof
I have this same problem and have been wrestling with how to deal with it for months. I thought my only viable option would be to pay the shop. How did you get the van from and back to the glass shop without the wind shield? Tow? Drive super slow?
 

220629

Well-known member
If your windshield doesn't need replacement there may be an alternative.

Few are rusted as badly as my 2004.


Windshield Rust Hack Job

https://sprinter-source.com/forums/showthread.php?t=36676

I plan to use a similar process with poly sealant on my rear windows of the 2006. I'm not willing to remove the rear windows. The van is basically rust free, but the inset around the rear windows has some rust which could easily continue to spread.

vic
 
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quillaja

2004 2500 140WB high roof
If your windshield doesn't need replacement there may be an alternative.
My windshield is cracked and needs replacement anyway. I was thinking of having a body shop do all the work, with insurance covering the windshield and the paint out of my pocket. But I'd rather repair the rust myself and keep my money if possible--I just don't think I can handle the glass replacement myself.
 

Midwestdrifter

Engineer In Residence
I've replaced a few old style rubber gasketed windshields, but with the newer glued in units that's not something that I would attempt either.

vic
I have done a couple, its very fiddly, you need to get the right height bead and correct placement, plus you have a limited window to do it in. There are no mulligans with bonded glass... With the sprinters windshield being so large and high off the ground, I would not even attempt.
 
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220629

Well-known member
I to am interested in how you got the vehicle home from the glass shop? just drove it?
:idunno:

I don't see it as any different than riding a motorcycle down the highway. Just wear your sunglasses... and maybe a helmet.

vic

Added:

RCW 46.37.410
Windshields required, exception—Must be unobstructed and equipped with wipers.
(1) All motor vehicles operated on the public highways of this state shall be equipped with a front windshield manufactured of safety glazing materials for use in motor vehicles in accordance with RCW 46.37.430, except, however, on such vehicles not so equipped or where windshields are not in use, the operators of such vehicles shall wear glasses, goggles, or face shields pursuant to RCW 46.37.530(1)(b).

http://app.leg.wa.gov/rcw/default.aspx?cite=46.37.410

Other states have similar regulations.
 
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TJD

Member
Hey Doug-Thanks for the thorough write-up. I'm going to tackle the job over the upcoming Labor Day weekend. I have all the products you suggested, glass company on board to come back and replace the glass 3 days after removal. My 2004 has the rain sensor windshield which inflated the project cost substantially. It's been cracked for years so it's time. I'll let you know how it goes. Thanks again
 

lindenengineering

Well-known member
Sorry whattah palavah!

I /we simple cut the whole freakin area out, with die grinder /sawzall & weld in a "new" repair section then prime and re- paint !

I am about to do this again then crush another donor van shortly!

Making room for more Landrovers on the road!:lol:
Dennis
The Sprinter cannibal me!
 

windseye

Member
I have this same problem and have been wrestling with how to deal with it for months. I thought my only viable option would be to pay the shop. How did you get the van from and back to the glass shop without the wind shield? Tow? Drive super slow?
Safelite did the job in my driveway
 

Gaspiper

Active member
Just Had the windshield replaced after removing rust around the old one and painting the effected area especially on the bottom which makes me wonder why did it only last three years since the same job was done in 2013 ? My body shop guy used the same glass company to remove ,get all the work done then install a new glass.
I believe rain water was collecting at the bottom of the windshield and not draining away that caused the rust as I remember every time it rained my note pad and any paperwork sitting on top of the cluster close to the edge of the windshield would get wet !!
 

Arnie_Oli

Member
I am looking to do this as it's one of the few places we have rust now. I have an 8.5mm "anti-bandit" windscreen fitted which is no doubt very heavy to remove to add to the joys though. This si down to us having an ex services vehicle with added toys on it.
 

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