Recommended roof corrosion repair, DIY

[oak]

Hi.

I live in Norway and have a 2007 California. I see some signs of the roof corrosion problem (blistering on the front roof panel, and around the roof top perimeter under the rubber seal).

Since being a 2007 model I assume I have to pay for any repair myself. For my whole life I have mostly maintained and repaired my cars myself so I have some general experience with mechanical and corrosion/paint rework.

On this roof issue however it seems like a "normal" corrosion job is not sufficient (keep in mind I have not read through every topic on the subject).

So I guess if I am going to attack this problem myself, is there any guideline/lessons learned available on how the problem should be approached, what improvements should be made etc?

 

[Deskman]

I'm curious too.

 

[WelshGas]

Hi.

I live in Norway and have a 2007 California. I see some signs of the roof corrosion problem (blistering on the front roof panel, and around the roof top perimeter under the rubber seal).

Since being a 2007 model I assume I have to pay for any repair myself. For my whole life I have mostly maintained and repaired my cars myself so I have some general experience with mechanical and corrosion/paint rework.

On this roof issue however it seems like a "normal" corrosion job is not sufficient (keep in mind I have not read through every topic on the subject).

So I guess if I am going to attack this problem myself, is there any guideline/lessons learned available on how the problem should be approached, what improvements should be made etc?

Firstly, this is Not " Corrosion " in the normal sense of the word. It is Galvanic Corrosion and is Non-Structural and basically Cosmetic.
It is caused by 2 Electrically dissimilar metals in the presence of an electrolyte, in this case Water. The metal parts of the roof are an Aluminium Alloy and there is an Internal steel gripper clip within the rubber seals. Those are the 2 metals.
This was a common problem on the old Landrovers. Aluminium body panels and steel frame.
There is a posting on the T5 Corrosion thread where an owner, similar aged vehicle to yours, had a repair that basically involved smoothing off, high zinc primer then sprayed to match. It cost £400 .

I would suggest finding a GOOD body shop, one that specialises in vintage vehicles etc:, not a simple accident repair shop.
Replace any seals that you can, especially around the elevating roof and front section. Rub back, high zinc primer, smooth down, undercoat and top coat. With an older vehicle matching colours might be difficult so consider going 2 tone . eg: grey vehicle/black roof or something similar.

Your vehicle is 11 years old. A good repair/re-spray should last AT LEAST 5 or 6 years or longer and could then be repeated if necessary.

Post 3888

https://vwcaliforniaclub.com/thread...of-corrosion-general-discussion.9000/page-195

 

[Dorchest]

Hi Oak

I’ve got the same age California as you with the same corrosion issue that seems to be getting much worse recently.

What did you do in the end? I’m like you and can fix things so I’m keen to save some money by fixing it myself.

All the best for 2022.

Regards

Mike Jones
Dorset

 

[Ozzy Pete]

Hi Oak

I’ve got the same age California as you with the same corrosion issue that seems to be getting much worse recently.

What did you do in the end? I’m like you and can fix things so I’m keen to save some money by fixing it myself.

All the best for 2022.

Regards

Mike Jones
Dorset

I had mine done under warranty but there’s no reason you can’t do it yourself. When they did mine they marked where the top of the seal goes and then stripped off the paint under that mark. I’m not sure if they did the front of the roof as well as it would be more difficult to get to and you would need trestles and planks. They then painted it with some sort of aluminium corrosion inhibitor then glued the New seal in place as this is supposed to prevent any water ingress which without water galvanic corrosion shouldn't occur. It’s been done over 3 years now and I check the roof just above the new seal on a regular basis and seen nothing.
Obviously it’s a job that requires some care but no reason someone with good DIY skills couldn’t do it successfully..
I’m not sure how much a new seal is through VW, probably not cheap
But I have seen genuine new seals on Ebay for £70-£80.

Obviously if you have corrosion that has gone above the seal then this method may not work for you. But if it’s just small areas then blowing in the paint should be fairly straightforward.

 

[Dorchest]

I had mine done under warranty but there’s no reason you can’t do it yourself. When they did mine they marked where the top of the seal goes and then stripped off the paint under that mark. I’m not sure if they did the front of the roof as well as it would be more difficult to get to and you would need trestles and planks. They then painted it with some sort of aluminium corrosion inhibitor then glued the New seal in place as this is supposed to prevent any water ingress which without water galvanic corrosion shouldn't occur. It’s been done over 3 years now and I check the roof just above the new seal on a regular basis and seen nothing.
Obviously it’s a job that requires some care but no reason someone with good DIY skills couldn’t do it successfully..
I’m not sure how much a new seal is through VW, probably not cheap
But I have seen genuine new seals on Ebay for £70-£80.

Obviously if you have corrosion that has gone above the seal then this method may not work for you. But if it’s just small areas then blowing in the paint should be fairly straightforward.

Thanks for the info Pete. Looks like a job for the summer! Cheers….. Mike