450SLC Passengers floor surface rust

Back in March, I discovered how wet the passengers floor was in my 450SLC.   Over the time water was getting on the floor, it had started some surface rust.    It appears that at least some of it was coming from the A/C drains.   I still need to test a hose on the windscreen and cowl drains to make sure water is not getting in from there too.

Obviously the most important thing is to fix the source of the water.   I also felt it was important to fix the surface rust on the floor.   It still wasn’t too bad, so I used a wire brush attachment on my drill to grind it down.  This removed all the loose rust and debris so I could treat it with rust guard paint.

I applied the rust guard paint with a brush.   I didn’t want to use any spray products in the cabin for risk of overspray on carpets or the rest of the interior.   As the floors will not be visible once the sound deadening, carpets and floor mats are in place, it seemed a better way to go.

As the floor had been body colour before I started grinding it down, I purchased a couple of pots of colour matched paint to do a top coat.   This isn’t strictly necessary.  As given I am doing it with a brush it was going to be obvious it wasn’t factory.  However, I thought it would also protect the paint and overall look like a better job.

For a home job I am reasonably satisfied.   I probably could have spent a bit more time on prep, but this is an area that will not be seen.   Given the 107s propensity to rust, I am hoping it will offer much more protection to the metal than before.

Now the floor is repainted I will put the seats back in and take the car on a test drive.  This will help me see if I have fixed the condensate leak.  It will be harder to test now the weather has cooled down.   I’ll also wash the car without the carpets in place to see if any water gets in around the windscreen or cowl area.     I may need a new windscreen seal as well.   It has not been done since I owned the car.