POR-15 for bubbling paint

[oilpsi2high]

My nearly 9 year old car is starting to show it's age. I have paint bubbling on the bottom of the doors, the wheel wells are starting to bubble up, and so is the trunk lid. I'd like to try and slow the rust down since the rest of the car is still in good shape. My plan was to use a wire wheel to clean up the bubbled areas, then do the por-15 regimen as a primer. Then coat that with color-matched paint and finally clearcoat on top of the color.

Has anyone had good results with POR-15? Ever tried a different yet similar product? My car sees salt of course so I'd plan on doing this repair in the fall before the snow flies. It's too hot and humid to paint now.

Thanks fellas.

 

[doitmyself]

If your rust has bubbling paint like the picture below (left), it means that the rust has started inside the weld seams (right) and is working its way out. Wire brushing and coating it will only mask the problem, not stop it.

I'll let someone else talk about rust converters, oil sprays, and other techniques to attempt to slow down the rust. If your rust is surface only (not bubbling), then you have a chance at slowing it down.

This is what happens when salt solution gets into galvanized sheet metal seams. If you plan to keep a car in good condition past 8 years in the salt belt, I am becoming an advocate of rustproofing oils. I just had my car resprayed today at Stateline Krown in Monroe, MI.....excellent service (cheap plug

to benefit other Michiganders).

 

[oilpsi2high]

The door is only surface rust where the paint wore away from the edge that touches the weatherstripping.

The wheel well lip is more of a bubble.

 

[stevejones]

Originally Posted By: oilpsi2high

Has anyone had good results with POR-15?

No. Looked good when applied, but you can't "convert" rust.

 

[NHGUY]

GM car?

 

[Vikas]

a Mazda?

 

[oilpsi2high]

GM car, 2007 model year built on 11/06.

 

[oilpsi2high]

Here's what the wheel well lip looks like now. Will POR 15 help slow it down or should I get ready to buy a new car in a year or two? About a year ago this spot was the size of a penny:

 

[Brad_C]

The only way to stop rust is to prevent moisture getting to it. POR15 is nice in that it creates a great seal *if* you can get it to bond properly. If there is any way that moisture may possibly reach the metal then the rust will continue to form and just blow the POR15 off the surface. It won't slow rust and it won't stop rust unless you can completely isolate it.

Personally I get much better results from fish oil and some compatible top coat, but horses for courses. I have had some luck with POR15 on surface rust. Completely removed the rust with sulfuric acid and used POR15 to seal the surface, but to be honest any compatible paint coating would have done the job.

The biggest advantage of POR15 is being moisture cured it will draw out any remaining moisture from the surface being coated and lock it up in the polymer. It is fussy about what it bonds to and the recommendation of a light surface rust coating to bond to is because it is a better mechanical bond than chemical.

 

[oilpsi2high]

I'm going to give it a try before the snow falls.

 

[iluvhonda]

I might comment on the bottom of the doors is that water is sitting on a sill and rusting it out. I have a car that has a rotting door seam like in pics because it was in a accident and never aligned correctly. Finally noticed it when it was too late.

If you have touch up paint I would do those small areas after you clean them up with some abrasive paper. Wouldn't go too crazy if your unloading the car in the future.

I've used POR 15 on my door seams because both paint from can and door were black. It masks the rust for a while but it's come back.

 

[buck91]

Used the 3 step por-15 process on a rusty machete blade. Has held up amazingly through general purpose camping and firewood gathering including light splitting. Over about 6 years.

Not perfect, but very good.

 

[Trav]

Originally Posted By: oilpsi2high
Here's what the wheel well lip looks like now. Will POR 15 help slow it down or should I get ready to buy a new car in a year or two? About a year ago this spot was the size of a penny:

Are you sure that's metal? It looks like the plastic wheel arch trim GM uses on some models.