POR15 still the best for floors?

[Austrianvespaguy]

Cleaning up the interior and almost have all of the old sound deadening removed. Just one quarter sized rust hole on the passenger side so thankfully nothing major! Is POR15 still the go-to coating for resealing floors these days? Lastly, how do I go about getting the big floor plugs back in properly? Can I coat both the floor and the plugs and then just pop them back in, or is some sealant between the two necessary? Thanks!

[Austrianvespaguy]

Picture for reference:

[Lugnuts]

Used this to seal a small section of floor pan I had to cut out/weld:

https://www.rustbullet.com/automotive-applications

Only a small scale application, but seems like a decent product.

[jeffnhiscars]

After using POR15 to stop rust you can use the goo with fiberglass mat to seal up holes. Wear gloves though as it it has to wear off your skin

[rturbo 930]

I think people use POR15 in a lot of cases where they shouldn't. POR15 is a rust encapsulator, and is designed to be used on rusty surfaces. From what I hear, it actually doesn't work well on clean and pristine surfaces, and sometimes will peel off. I've also heard that it is very difficult to remove if, for whatever reason, you want it gone later on. It's not a one size fits all product, rather, it's a product for a specific situation.

I would repair the rust hole with new metal, treat any surface rust with naval jelly (Loctite makes some), and then prep it and prime/paint over it normally.

[jrobie79]

I've used chasis saver rust paint pretty for pretty much all my rust repair, its been holding up great over the past 3 years

[cscracker]

After going through a few different strategies trying to repaint some parts on the underside of my 533i, I ended up using Rustoleum truck bed liner with excellent results on a cover plate that goes on the bellhousing under the engine. It's not as thick as you'd actually want on a truck bed, so it's not too heavy, and it's a really tough coating. I cleaned up the metal with roloc scotch brite pads and a die grinder, primed with self-etching primer, and sprayed the bed liner on.

If you can clean up the metal, I recommend this approach. Obviously a floor is a lot larger than a little cover plate, so it's a big task. Roll-on bed liner is probably easier to use for this application than spray-on, too.

[jrobie79]

If you want the best undercoating you can't beat 3M Body Schutz. It's the OEM stuff for a bunch of manufacturers. You can get a cheap gun for it on eBay, shit is nails. Better than anything I've ever used from an auto parts stores

[tomstin]

I have used POR15 on surface rust and surrounding areas and it seems to hold up very well on both. Like any paint project, preparation is key, and with POR15 it is CRITICAL. Along with following the directions to the letter. I let the area dry overnight after cleaning and prep. It can be a bit finicky to work with but done properly, it works very well.

Get a box of disposable gloves, once that stuff gets on you it is very difficult to remove. Add to your list, disposable brushes, use them once then toss them. I recommend purchasing the 6 pack of little containers. Once you open the can, the re-sealed can does not store well.

[TobyB]

As to the plug, I'd seal it with seam sealer, like the factory did.



t

[noid]

Rust bullet then cosmoline over top.

[15Michaeljoseph]

I used Eastwood brush on rust encapsulator on my floor.

Sent from my moto g(6) using Tapatalk

[zaq123]

Cleaning up the interior and almost have all of the old sound deadening removed. Just one quarter sized rust hole on the passenger side so thankfully nothing major! Is POR15 still the go-to coating for resealing floors these days? Lastly, how do I go about getting the big floor plugs back in properly? Can I coat both the floor and the plugs and then just pop them back in, or is some sealant between the two necessary? Thanks!

Why por15? It's ok when you are trying to seal the rust but sealing the rust it's not the ideal route if rust can be removed. I would just wirebrush any surface rust and used the epoxy primer and paint to treat the exposed metal.
Also why everyone go as far as removing factory body plugs and OEM deadening material? You will never do it as good as OEM, no matter what yo do. If there is no rust (like in your pic), let it be. Not only it will be OEM original but will last another 30 years.

I had two rust holes in my floor, one in the passenger front side (exhaust heat shield stud) and one on the passenger side of the middle console. I cut, welded 1.5" sheet metal patch and primed/seam sealed/primed/painted it. Console side rust repair was a little more complicated since there is a transmission mounting rail/panel welded from the under the car. No way to access the cavity to treat welded patch from under the car. I elected just to cut the rust out in the shape of rubber firewall/floor plug, treat edges with epoxy primer/paint and plug the hole with the rubber plug. You can find all kinds of plugs that are about the size of the rust spot.
My jeep has rubber plugs all over the floor by design with no issues of any kind. They make hosing down the floor very easy job.I think it is obviously much better approach than welding patch and not be able to treat the weld

[zaq123]

POR15 still the best for floors?

1st, 2nd pics, round sheet metal patch welded, exhaust shield stud welded to its center under the car, all welds wirebrushed, primed with epoxy primer, seam sealed, primed again and painted to match the body color.

3rd pic is the rubber plug approach (plug is not installed yet). You can see from the pic why welding is not the best choice here. Plug will be installed with tar cord, similar what BMW uses to seal gas filler boot to the rear quarter panel.

No more rust on this car. The body is in excellent shape for the northern car.





Sent from my iPhone using Tapatalk