Let's talk chassis/under carriage cleaning, coating and painting

[2000xp8]

So i have the tank out to swap in a holley 12-347 instead of my dual external pumps.
While i'm waiting for some fittings and the tank is uninstalled i want to clean up that area and coat or paint.
Only some surface rust and oil and fluids.
I plan to do the whole car, but right now i have to get this done quickly so i can reinstall the tank this weekend.
I do have a car lift, so i won't be on my back.

So far i used my Milwaukee 12 die grinder with a wire wheel and a hand brush to get most of the surface clear of loose debris.
Still need to degrease and do whatever it takes to prep it.

My car's undercarriage is in relatively good condition. No rust, probably from 30 years of fluid protection.

I would kinda like to do the underside flat gray and the wheel wells black.

Not sure i'm i really need to go por15 crazy on it. Since it's always garaged even my subframes that i painted 15 years still look good.

Don't shoot me on this one, but i was kinda thinking aerosol?

When i did the torque arm i had to clean the rear where the dogbone was. It was a mess, i over sprayed brake clean and it cleaned the hell out of the floor pan.
Is it safe to just spray it under there? It was so easy i just don't know what that stuff does to metal, paint or whatever the hell is on the undersized of the car.
I don't mind laying out some plastic and just going nuts if it's that easy. I could literally watch the grease disappear effortlessly.

Not turning this into a show car, but i do walk under the car all the time (lift goes high enough for me to pass without ducking) and i've spent 10 years thinking about cleaning it.

Thoughts?
Products?

 

[mustang90]

Por 15 is some really good stuff and I have used it in the past. You can always use some frame epoxy paint too which is cheaper. On my car which I’m going show, I prepped underneath and then applied adhesion promoter, etching primer and raptor bed liner. Came out nice and durable then reassembled the car adding powder coat etc.

 

[mustang90]

Here are some pics

 

[mikestang63]

if you don't have any rust, then I would think using a good rattle can primer and then rustoleum would work potentially, however, POR 15 is much more durable and will hold up to the weather, rocks, and wear better IMO. I have also used spray Eastwood chassis saver for hard to reach places, frames, etc. That stuff however flows like water and seeps out of every crack and cranny and drips everywhere.

 

[2000xp8]

Thanks guys.
Mustang 90, you and I are on opposite ends of the spectrum, lol.
I just want to neaten it up a little with the tank out in. Nobody will see this other than me.
Underside of your car looks amazing. I'm going to throw a constructive criticism at you (don't be insulted), lose the red tank straps, some parts aren't meant to be accentuated. Other than that, love what you have done.

Mike, i was kinda thinking rustoleum in a rattle can.
This car never sees rain, most likely it would get wrecked.
Drag radials, 3.73 gears and all the power coming on at 2500 rpm make it undriveable in the rain.
So i'm not really worried about the elements. Hasn't been my daily driver since around the year 2000.

Before i get to painting, i have to get done with the cleaning anyway. What did you guys do to degrease and clean the underside?
Think i can just blast it with brakeclean? My buddy has an entire cabinet full of it, so I wouldn't be wasting money (my money at least) and i know it works fast and easy.

 

[Mustang5L5]

I did mine in POR-15, but I think that was a mistake. Here's why.

POR literally means "Paint-over-Rust", but the underside of my car was rust-free. I cleaned and degreased it and was left with the typical ford grey undercoat spray across most of the underside. There was some areas of light rust, but for the most part it was clean, smooth metal that had clean paint over it.

I painted it with no prep other than degreasing. It held nicely for about 6-8 years or so, but now it's peeling off in sheets. I can go under there and peel it off, but only in the areas with clean metal/undercoat underneath. In a way i'm kinda glad, because I like the idea of having my clean underside again, but wish it was consistent.

In contract, i painted my rusty rear axle in POR-15 and it has held up great. I can jack on it, put it on jackstands and it stands up fine.

 

[Rdub6]

I have had some good luck with a combo of Rustoleum rattle can as well as brush on. My car sees no bad weather and isn’t driven much, but it has held up great for what I put it through. I also chose to do the wheel wells black like you mentioned. That was rattle can as well.
I will say that I cleaned and prepped everything thoroughly, and hit most of the areas with scotch bright, then primed, then paint.

 

[limp]

While my car is rust free, I thought I had some surface rust on the bottom of it and started wire wheeling some areas of it.... Turned out to be more rust color in the dirt on the bottom even after I had pressure washed it......
I then switched to RED scotch brite soaked in Paint thinner.... Cleaned it up like new....
If you find some surface rust you could touch up the area with a wire wheel....
Then spray the bare metal areas with light coat of Etching primer, follow up with some " hot rod primer", then follow up with some paint...
I used a darker grey rustoleum color for ;paint..... Pleased with the results....
Was not looking for a Garage Queen look, just cleaned up and painted for any future protection from the elements.....

 

[General karthief]

I like the idea of having my clean underside again,

Just whip out that Bissell again

 

[limp]

Just be forewarned, sometimes things get out

of control

 

[Rdub6]

Just be forewarned, sometimes things get out

of control

That’s awesome! One time I’d like to do a complete tear down and rebuild. We’ll see if that happens some day!!

 

[limp]

That’s awesome! One time I’d like to do a complete tear down and rebuild. We’ll see if that happens some day!!

18 years of my life.......

 

[2000xp8]

Thanks guys, I had a feeling to pass on the por15.

Rdub, that's pretty much what i want to do.
I have all next winter to do the rest of the car, right now i just need where the gas tank goes back.

I hadn't thought about scotch brite, red or green for just surface rust?

 

[RaggedGT]

I used purple scotch brite pads and wax and grease cleaner for prep- High temp engine paint rattle cans-has been holding up really well. Car sees all sorts of weather and outside storage in the warm months

 

[limp]

Thanks guys, I had a feeling to pass on the por15.

Rdub, that's pretty much what i want to do.
I have all next winter to do the rest of the car, right now i just need where the gas tank goes back.

I hadn't thought about scotch brite, red or green for just surface rust?

I used Red on my car.....

 

[evintho]

On my '89 I just pressure washed the whole undercarriage really good then sprayed on some rubberized undercoating in a can. Took a couple of cans but lasted for years.............

 

[Rdub6]

Thanks guys, I had a feeling to pass on the por15.

Rdub, that's pretty much what i want to do.
I have all next winter to do the rest of the car, right now i just need where the gas tank goes back.

I hadn't thought about scotch brite, red or green for just surface rust?

Funny thing is, when I had the tank out, all I did was clean, and never painted. Then when I decided to do floor pans, and things got a little crazy, as @limp suggested it can, I went nuts with the cleaning and painting. So at some point, I have to drop the tank again, and get that painted to match. My fuel gauge is acting a little weird, so that may be sooner than later.

 

[Rdub6]

On my '89 I just pressure washed the whole undercarriage really good then sprayed on some rubberized undercoating in a can. Took a couple of cans but lasted for years.............

That’s real nice! Clean, simple, and functional!

 

[Noobz347]

Thanks guys.
Mustang 90, you and I are on opposite ends of the spectrum, lol.

My reaction was, "Holy !" but yours is funnier.