Rear Underbody Corrosion & Heat Shield Replacements

[DickP]

Hi

The past winter has not been so kind to the underside the Clio 182. Underseal has been damaged or hardened and split, allowing water in and this has caused areas of corrosion around the rear parts (i.e. boot floor and structures either side). The rear heat-shield is also corroded from bimetallic corrosion around the exhaust mounts and it already has the larger washers installed by the previous owner for the other fixing points.

For those who like to keep the body shell in good condition, how do you remove the factory under seal and what have you applied as a replacement coating?

For those who have had to replace the heat shields, what products have you used? Do those who race these have a better alternative perhaps?

Thanks!

 

[DickP]

Hi

Has no one had to deal with this yet then?

 

[Brigsy]

Knotted wheel on a grinder will remove factory underseal no bother. Beware its messy and time consuming, wear goggles as a trip to the eye infirmary is not nice (from previous experiences !)

I would spot remove underseal where the rust is forming, clean up with knotted wheel, if metal is thin or holed might need welding so be prepared for the worst. Treat with good rust convertor when sorted (look at bilt hamber products) zinc primer on top, epoxy on top of that and paint.

You can also get away with rust treatment products, have used por15 kit before, basically the same clean up metal, clean with the cleaner/degreaser, use the metal prep and paint over with black por15. It works ok when applied right will slow down/encapsualte the rust.

 

[DickP]

Hi

Thanks for the comments. I think I will follow your suggestions.

What would you suggest about the heat shields? Do you know what the people racing these cars do about the rear most heat shield?

Thanks

 

[Brigsy]

You can take the heatsheilds off without any problems usually...you could fit some reflective heat shielding or similar if worried about it. Most motorsport places sell a variety of heat management products.

 

[MRBILLYUK]

My rear heat shield had coroded through in places and a couple of the bolts had snapped off completely . I'd already put larger washers on the bolts that were still useable . I covered the heat shiled with this CT1 sealant / adhesive and stuck it back and it's been fine since and no rattles . It's not cheap but it's good stuff .
https://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=CT1+SEALANT&_sop=15