C8 sill corrosion and repair - wheelarch sealant missing

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aea_s
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C8 sill corrosion and repair - wheelarch sealant missing

Post by aea_s »

Hi All,

I thought it might be useful to post a few images here concerning the recent repairs I made to our aging C8!

The MoT tester noticed that the O/S sill was going rather thin at last year's MoT; not thin enough to fail but it was weaken to a point where I needed to look at it and effect a repair before this year's MoT. This was a bit of a surprise to me as I though the C8s were fairly well rustproofed and if any part of the bodywork would fail, it would likely be the N/S - the side nearest the verge, where all the water an mud sits in the road.

Upon investigation after a pressure wash, I noticed that on the O/S there seemed to be a finger-sized entry point for crud to get in where the layers of sill metalwork meet the rear arch. The body sealant was present and complete on the N/S but not on the O/S, hence the hole through into the sill. So over time, water, mud and detritus and had corroded the sill from the inside out. All that was left was a paper thin layer of steel, masked completely by the original paint!

Anyone with a C8 reading this might take a moment to check their wheelarch sealant is there and doing the job as intended!

Here are some photos of my repair. I haven't painted it yet as it's too cold outside at the moment. Will also 'XCP Rust Blocker' spray the insides of the sills with a lance in the summer for extra corrosion protection.
Rust cut out of sill, zinc rich primer applied inside section
Rust cut out of sill, zinc rich primer applied inside section
New steel crudely shaped to match the hole and clamped in place
New steel crudely shaped to match the hole and clamped in place
Mig welded (with CO2) in place and ground back
Mig welded (with CO2) in place and ground back
Inside wheelarch, looking forwards. New flexible body mastic to seal panels - should have been done correctly at the factory
Inside wheelarch, looking forwards. New flexible body mastic to seal panels - should have been done correctly at the factory
Repair completed and primed, ready for paint in the summer
Repair completed and primed, ready for paint in the summer
Hopefully this will keep the old girl rolling for a while yet!
All the best,

Andrew
Andrew/Drew
2013 Nissan Leaf
2008 Electric Vectrix (2 wheels!)
2006 C8 Exclusive
1994 BMW F650
1964 SIIA SWB 2.25D Landy - cherished but used
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Making tin cans;
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1998 Xsara 1.9 TD Exclusive 260k miles
petarc1971
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Re: C8 sill corrosion and repair - wheelarch sealant missing

Post by petarc1971 »

Well done, it would be good to do the interior with liquid wax.
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