How to deal with rust bubbles due to water leak in boot

[Slapster]

Hi all, I've recently become the proud owner of a 2006 mk2 Focus 1.6.

However, I've discovered a leak from I think the tail light leading to a collection of water in the spare wheel well. The protective mat was soaking! I've sealed under the tail light and the silicone is drying as I'm typing. Once dry I'll check that the leak has been fixed.

However, there are numerous bubbles of rust starting to develop in the well. I would welcome advice on the best way to deal with this as a relative novice to this kind of work. I've. I've attached a couple of photos of the rust.

Thanks in advance for any advice offered.

Mark.

[theredfox]

sounds as if water has been lying in wheel well for a while for rust to form

rub back to bare metal and buy/use rust stuff to stop it the use rattle can

[chemfusion]

You could rub down the patches to remove any flaking paint/loose rust, clean with spirits and treat with something like Hammerite Kurust (contains up to 10% tannic acid* which reacts with the iron forming a more stable material) and then paint over? Or rub down and then apply direct-to-rust paint perhaps

Worth checking the underside as well in the same places to see if it has penetrated.

*almost the same stuff that makes tea brown

[Slapster]

Thanks for the advice. I used a wire brush, followed by some wet and dry and then used a direct-to-rust spray which luckily my local store had in silver. 

I'm chuffed with the results. Now fingers crossed that I wont find any leaks when testing tomorrow.

Thanks a bunch, Mark.

[chemfusion]

Nice, looks great!

[Slapster]

Wahoo,my car no longer leaks!. Many, many thanks for your advice. 

I figured whilst I was at it I may as well seal both tail lights and came across the unused orange electrical connector mentioned in one of the tutorials. So my next project is to hook up an extra power connector in the boot. I am so glad I found this website!

For future reference here's a link to the youtube video (starting at 9 mins) I used which shows the exact fix needed to arrest the leak...