Today I removed the rear bumper and wheels to start the process of treating the rust and applying fresh body seam sealer and stone guard paint in the arches and the rear panel and chassis. My god, this car has rust everywhere! What is really apparent is that many of the panels do not have seam sealer added so moisture/water can penetrate between them. What really surprised me is the rust under the boot seal and the attempt possibly by the dealer to cure a leak by adding silicon sealer under the boot seal. I will add kurust to the rust, and then apply stone guard. On th rear panel behind the bumper I will also add a coat of the original colour just to give it a better look although it will not be visible with the bumper fitted. This is not a fix to the rust issue but just an attempt to slow it down. I know it will return. But if what I am doing will extend the life of the car it is well worth the effort. I have added some pics for reference.
That is an incredible amount of rust. I am especially shocked by the condition of the boot lip under the seal. Perhaps the seal was fitted with an acetic acid cure silicone? Neutral cure silicone or polyurethane should always be used - if appropriate. I use Wurth and Sika products on my vehicles.
I am not sure why they used silicone sealer under the boot rubber anyway, do you think it was leaking water into the boot from under the rubbers? I think I will reseal it using panel sealer and then paint over it. I have to say I have worked on much older Alfa's with less rust. I find it hard to believe its just down to salt on the roads in the UK. The whole paint process and stone guard looks very poor. Hardly any primer and a thin layer of top coat and stone guard on limited areas of the arches. Anyhow, it will keep me busy over the weekend.
Silicone should not be required under the boot seal. There is none under my seal. I agree with the very minimal paint and protection applied to the Copen. The Copen is a bit disappointing after working on vehicles with galvanised bodies and fully coated and corrosion protected chassis. Perhaps Daihatsu were constrained with a limited production budget, combined with a short expected lifespan for their Kei car, and built accordingly?
MultiplexMan, I have noticed the paintwork behind the bumper etc has little of no clear topcoat lacquer, is this correct? Cheers
I think the paint finish varies between production runs. My Copen has very thin paint. I doubt if there is even a separate clear coat on top of the base white as I get colour even when I use clay. Finish could have simply been one coat of gloss white. I am very careful when cleaning and applying polishes and sealants. A lot of areas under trim are only dusted in primer. Some sections behind the seat belt anchors were raw. I am undecided whether I will keep the Copen long term - that is, at least another 20 years. If so, I'll have to give it a full strip (trim off but perhaps not windows pending availability of rubber seals), spot repair and paint as I have done with classics I have previously restored. A tough call between care & maintenance and full preservation. I sprayed Wurth corrosion protection followed by cavity wax when I first purchased the car. I also took the opportunity to coat areas with Wurth Stone Guard/Underbody Protection ("Schutz"). So far so good. I have noticed stone chips will spot rust if you do not get to them quickly. The Copen is a great modern microcar. It may not have the outright uniqueness of my old Messerschmitt KR200, but it is so much more driveable.
I used a german product called "Fluid Film" (kind of a cavity wax like mike sanders, but it does not harden) followed by "Perma Film" (used for corrosion protection on ships) on the underside. Since then I did not have problems with rust and I am pretty sure the car will last for the time I want to drive it. Maybe not 20 years, but who cares?
Mission accomplished. It took me a couple of days but I removed the rust from the back end, arches and chassis and applied the rust inhibitor, Kurust, prepped and masked up the area. I then sprayed wurth stone guard under the arches, back end and the entire under chassis etc. I also placed body seal wherever it needed it. I also placed a small strip of stone guard areas on the lower part of the inner arches which are prone to stone chip and rust. When the stone guard had dried I applied 3 coats of base coat of the cars colour and 3 coats of clear lacquer. I think its looks tidy and I prefer this than the tar like under seal which remains tacky. I have uploaded some pics of the work.
Need your advice guys, I noticed that water enters the boot and I think it's coming from under the boot seal. Previously it has silicone sealer under the boot seal which I removed because it ate into the paint and caused it to rust. Do I need to reapply some sort of sealer between the metal lip and seal to stop the leak and if so which type is safe to use on paint etc. has anyone else had this issue? Cheers.
