Battery Tray in OK shape?

[Tbonem3]

That's not too bad at all, good cleaning. But no, I wouldn't leave that rust.

[antknee]

Correct...gray primer.

Here is how things currently look after removing the black tray, vacuuming out the area and cleaning up the rest with All-Purpose Cleaner and some towels:

















Wondering if I should I leave it, as is. Is it overkill to use some wire brushes to get rid of the remaining rust and perhaps treat the area and primer it? Thoughts?

me personally i would still treat it. Looking at it post-clean up, i would approach it differently now.

I would just hand sand the rust spots, and prob treat it with some anti-rust primer and call it a day. I'm not sure a wire wheel would be needed just yet.

Def keep an eye on this though, as we all know how cancer rust can get.

[Mystic3]

Rust never sleeps.
fix it right, while access is easy, or regret it later.

[eacmen]

I’ve heard good things about https://www.fluid-film.com/

[antknee]

I’ve heard good things about https://www.fluid-film.com/

I’ve used this stuff too, but it gets gunky and messy. It’s good for preventing rust by spraying the undercarriage with it

[eforty6_m3]

Ended up using the POR-15 starter kit to address my rust.

Happy to report that the unexpected battery compartment/tray rust project is now complete. Using a combination of wire brushes, wire wheels, roloc abrasive discs, sand paper, dremel grinding bits and patience, I was able to achieve this final result (with brand new OEM battery tray installed):



I just need to add the 2 plugs (the original ones I ordered were the wrong size, so new ones should be arriving today) and this project will be 100% complete and in the rear-view!

Pretty pumped that the Coastal Grey Rust-Oleum Satin Protective Enamel topcoat did a fairly good job of matching the existing grey in that area! Again, NOBODY will ever see this, so it was more for me, but I'm happy with how it came out. Here are some progress shots I took (excuse the crappy lighting) along the way:

















After POR-15 Cleaner/Degreaser and Metal Prep:



After 2 coats of POR-15 Rust Preventive:



After 2 coats of aforementioned Rust-Oleum Coastal Grey Topcoat:




A reminder of before/after:

[Sharocks]

That looks great! I gotta check on mine now lol

[eacmen]

[heinzboehmer]

This thread made me check on mine too. Found some very slight bits of corrosion where the black bracket contacts the sheet metal. Ground those down to bare metal and added a layer of por 15. Problem solved.

Now just need to stop being lazy and finish fabricating the cover for my vincebar, so that I can give my whole trunk a layer of color matched paint.

[eacmen]

i painted the factory bracket red. cuz racecar.

at least +5 hp.

Also very brightly colored in case stewards don’t know where a bmw battery is!

[antknee]

awesome repair! now you sleep at night not worrying about it. Looks factory & most of all won't spread.

[Mystic3]

That kind of attention to detail is why our cars look like they do.
First class, well done.

[eforty6_m3]

Thanks for all the kind words, folks!

[Dripdrop]

Do you remember what plugs go into the battery tray area looking to get some but can’t seem to find which ones goes there

[eforty6_m3]

Do you remember what plugs go into the battery tray area looking to get some but can’t seem to find which ones goes there

OEM #41007140848 (20mm)