Refinishing Rear Door

My rear door is not as bad as I thought and can probably be saved. It is corroded on the bottom edge and the steel inner frame is rusty. That can be Kurust treated and painted. What can I do to save the Durabright outer panel. Lightly sanded down, skim of filler, etch prime and top coat? Have I missed anything please. Best filler suggestions would be great please…..thank you. John

You won’t stop the bubbling while the steel frame is touching the alli. Eventually it will dissolve away so don’t expect paint to save it. My front doors are similar and without removing the skin and getting a barrier between that and the frame I think I’m better off saving towards new doors. It’s a shame as the new skins are no match for the originals alloy.

Did my Ninety rear door 4 years ago after a bump with a gate broke the glass. Lots of corrosion with needing to renew lower rail and a couple of other sections. The door checker plate had done a good job of holding it together. A lot more work than sorting the lower end of a front door. A new door would have been a lot less work.
However the series rear door is a simpler structure.
If repairing yours is the choice Isopon P38 is a good filler and when all done a can of spray grease sprayed inside so it runs between the alloy and the frame will prolong life.

I have just replaced the rear crossmember for the second time. The first time I did it I cut out rubber rectangles to slip between the crossmember tags and the rear bodywork. They held up well and on removal no steel chassis was touching the aluminium bodywork.
Didn’t make any difference. The area behind the tabs was completely devoid of paint, left white and crusty. Obviously the corrosion traveled out from the securing bolts and didn’t stop, leaving perfect rectangular patches behind the rubber.
I think we can only slow this process rather than cure it.

my repair is here, and as bobsticky says on mine the steel bits touching the door were unpainted so porting a bit of corrosion, the door skin comes off quite easily and the new ones fairly cheap and easy to refit , while off allows you to derust, paint and insulate the steel from ally before skin goes back on , if you do need a repair section those easy to get too



i thought I’d repaired similar corrosion ok last year to rear wheel arch with epoxy and painted but bubbling again now , you’ll get a better job replacing skin if you have the skills