I have a 72 cutlass convertible with a replacement trunk lid from a 4 door cutlass sedan. There is some inner surface rust down by where the inner and outer sheet metal come together. What product would you folks recommend to convert / seal this to prevent that nasty ugly rot through?

Would not be averse to getting a composite deck lid if anyone knows of a good quality type available.

Thanks in advance!

finally retired and getting enough honet do's out of the way to start focusing on the car again.

 

https://ocean-supply.com/skyco-ospho...-osphoq-osp-4/

 

That looks like a good product. It has been a long time but years ago I used Naval Jelly. I googled it and got hits for several other products also. Evapo Rust is another good product.

 

I had this product years ago, then I finally ran out of it and when I went to buy some more I couldn't find it anywhere, I thought the company went out of business. I finally found it again but it's under this company name. I wonder if Evapo Rust is the same thing?

 

I placed my deck lid upside down on some sawhorses and poured Ospho inside. I carefully propped and tilted the deck lid so the Ospho would soak into each of the 4 sides where the outer sheet metal is folded over the inner deck lid frame. I put blue painters tape over the emblem and lock holes to keep the Ospho from spilling out; it was very messy so say the least, but I was able to soak it on all four sides. Do this on some plastic sheet and don't spill any on a concrete driveway as it will etch the surface.

If you don't know, Ospho is a type of rust convertor that turns surface rust (ferric oxide, FeO2) into iron phosphate (FePO4) which is a hard coating that turns the rusty metal black. I followed up with some rattle can undercoating sprayed as best as I could get into those areas to help seal against future moisture.

Rodney

 

I bought a new GM deck lid in the 80s and did similar to the above, but with a can of Rustoleum paint instead of ospho since it was pristine metal. I tilted the lid around so the Rustoleum flowed into the gaps in every seam.