m2geek 4 Report post Posted February 8, 2015 What is the best way to stop/slow the slight rusting i've got below the filler neck? Quote Share this post Link to post Share on other sites
Allanw 1071 Report post Posted February 8, 2015 It's a common E39 thing - at least you don't live in the UK, where the boot lid, wheel arches, sills and everything under the car rusts too! If its the normal stuff - you may find it never gets any worse for many years... but you could always scrape the top off, sand it back a bit, clean it up with some rust converter and more sanding, then etch prime it and go over it with some touch up paint. Quote Share this post Link to post Share on other sites
Toast 117 Report post Posted February 8, 2015 Sandblasting's really the only option if you're after something that will last. Sandblast it, rust neutralizer the previously affected area and then finish to your liking. That said once it's started (obviously depending on severity) it's not going to be easy to get rid of. It'll come back for sure if you do a "she'll be right" fix. Quote Share this post Link to post Share on other sites
m2geek 4 Report post Posted February 8, 2015 Went out and took a pic... Sanding that area makes me nervous, so I thought about hitting it with fish oil to stop it and then get it seen to when I can afford to have it properly done. Quote Share this post Link to post Share on other sites
BreakMyWindow 1874 Report post Posted February 8, 2015 That's not the rust people here are referring to. E39's usually bubble up in that area below the filler neck.. Quote Share this post Link to post Share on other sites
jeffbebe 1559 Report post Posted February 8, 2015 Doesn't look too serious, just a tiny bit of surface rust. As Martin says, it's not the usual nasty rust where water collects in the filler recess. Not even sure that's worth dealing to judging by the pic. 1 Quote Share this post Link to post Share on other sites
hybrid 1043 Report post Posted February 8, 2015 The galve coating on the metal ring/neck has failed probably from people over the year scraping it with the metal pump neck. Petrol is corrosive and would of done the rest.. the only way to fix it properly is to remove it and re coat. But you can just get a nice second hand one. Wire brushing it off is only a temporay fix as it will happen again. That or close the fuel cap and forget about it .. it wont in reality get any worse, its kind of only just surface. Quote Share this post Link to post Share on other sites
westy 614 Report post Posted February 8, 2015 It's gold passivated zinc plating. OOOOooo look how clever I am. Anyway, if it really bugs you, you could use some rust converter on it and spray it with one of the many 'rust treatment' spray cans. Quote Share this post Link to post Share on other sites