Who has used POR 15 ? Any tips or tricks

[Derek A.]

I just ordered some POR-15 to handle the door problems on the 535i. From what I understand they don't want you to dring down the rust. Just used the acid primer and then brush this stuff over it. Is that correct ?

[TimGinCentralNJ]

...some pretty decent instructions on how to apply it. I've always just followed the directions and had excellent results. You are correct, they say not to scrape/sand off all the rust...POR-15 needs something to 'grab' onto. You will want to put some top coat over POR-15 after it's dried because it eventually turns purple when exposed to sunlight for long periods of time. Again, this is all stuff covered in the instructions.

Another thing you might wanna' consider is leaving off the rubber strips indefinitely.

Good luck,
Tim G.
'91 535iM w/ no door strips


I just ordered some POR-15 to handle the door problems on the 535i. From what I understand they don't want you to dring down the rust. Just used the acid primer and then brush this stuff over it. Is that correct ?

[Unregistered]

if you have the original rubber moldings you will see a rusting piece of metal in it that is the cause of the problem. the new replacements (around $20) are all rubber. I put them back on to cover over the black por15 both to block UV and avoid repainting the door. no recurrence of rust.

[Derek A.]

When did the new deals come out ? I went through this about two years ago. Should I have the updated seals for the bottom ? I personally hate bodywork and am not very good at it. I like the seals as they cover up my handywork. Professional assistance is not in the budget for this project. :)