body and interior Undercoating - Anyone Applied?

[FrictionTape]

Today I removed the front and rear subframe and the vast majority of the car had a coating on it, similar to what you see here.

Is it the original from the factory? Would it be safe/wise, etc. to spray one of those rubberized coatings on the underside and over top the existing coating? Blast it off and apply?

Any insights are appreciated.

[TobyB]

While there is undercoating applied to most 2002's- more every year, from what I've seen-

the factory stuff was rubberized, and then painted over.

 

What you have there looks like it was done later.

 

As to overcoating it with more undercoating, (yes, that was fun to say)

it entirely depends upon what it is, and what you're gonna

shoot over it.

 

Easy test- shoot a small area, wait a while, then scrape at it.  If the undercoating

underneath doesn't soften, you're fine.  If it bubbles and gets soft, it would make

sense to remove the old stuff.

 

t

[tzei]

What Toby said

 

+ wash it well before otherwise it won't stick well.

[Conserv]

Many Rust Belt cars, in particular, acquired black(-ish) undercoating at or after they left the dealer -- products like Ziebart, probably the most-respected of them -- which, from the perspective of today probably didn't reduce rust as much as it hid rust. My '76, exceptionally low-rust for a Northeast car -- I washed the underside 12 months of the year -- has nothing but the factory undercoating -- over-sprayed at the factory in Polaris silver. My rust spots -- front fenders and a small box member outboard of the gas tank -- arose UNDER the factory undercoating, popping out only when they reached a critical mass, but suggesting that the factory undercoating didn't truly SEAL the underlying metal from water, salt, etc. These post-factory-undercoated cars, frankly, scare me, as I always wonder what is REALLY going on under that undercoating! Maybe nothing, but how do you know?

If this car is truly a keeper for you, I'd start by steam cleaning the underside to see what falls off and what adheres to the chassis.

Regards,

Steve

Edited September 19, 2015 by Conserv

[dlhoovler]

My '02 was Ziebarted when new--still has the stickers under the hood and inside the doors. And it's mostly solid--I think my dad was careful to touch it up for the short time he used it in the winters. It still wound up rusting a little in some of the usual places, but that was mostly where the undercoating didn't reach (double-thickness panels and the like). I'd expect that a few Pennsylvania winters would have done more damage without the rustproofing. But who knows--maybe it would have been better without it.

 

If I ever do a full-ish resto of the underside, it's getting all of that stripped off, any rust repaired and then no undercoating reapplied. Not gonna happen anytime soon, though.

 

-Dave

[jgerock]

I guess it depends on how far you want to take working on the car, your willingness to get dirty and how much the car will be driven.  Since I changed the color of my 69 from Nevada to Riviera, the bottom portions were not re-sprayed (at my direction).  I cleaned and scraped the bottom of the car then applied Eastwood undercoating.  It looks nice but has lost any "pop" from having powdercoated suspension bits against a body colored undercarriage.  I can live with it.  I left the inner wheel wells body colored.

 

[TobyB]

Having grown up in the land of the Calcium Chloride monster, 'undercoating' is really best described as 'underbody paint protector'.

 

IF the underside of the car is well- sealed, then adding the asphaltic layer protects the paint, which is what keeps rust out.

If you don't seal the underside, the stuff just gets lumpy after a winter or two.

 

On the first generation Subarus we drove into the ground, spraying the fall oil change from the tractors and cars onto the

underbody, then going flying down the dustiest dirt road we could find, seemed to be the best 'sealer' for cheap...

 

But you wouldn't treat a 2002 that way, so it probably doesn't matter too much.

 

t

[remout]

I guess it depends on how far you want to take working on the car, your willingness to get dirty and how much the car will be driven.  Since I changed the color of my 69 from Nevada to Riviera, the bottom portions were not re-sprayed (at my direction).  I cleaned and scraped the bottom of the car then applied Eastwood undercoating.  It looks nice but has lost any "pop" from having powdercoated suspension bits against a body colored undercarriage.  I can live with it.  I left the inner wheel wells body colored.

 

 

What was your process for getting the original material off? Did you do it all from underneath while on jack stands?

[PaulTWinterton]

Great pictures Jim!

 

I like this discussion.   Keep it coming.   I'm building up the enthusiasm to attack my underbody. 

 

There is still original Inka paint and primer under the car, but there are areas of surface rust that I cannot accept.    Add in undercoating, grease and grime and the job just gets bigger and bigger.

 

My first thoughts are to clean and grind/wire wheel down to bare metal.    Follow that with an Eastman or Por-15 process and finish with an oil-base polyurethane.    I know, I know, oil-based polyurethane is not car paint but it's brushable and creates a thick resilient surface to largely unseen areas.    Did I mention it's Inka paint?

Edited September 18, 2015 by PaulTWinterton

[2002Targa]

Great pictures Jim!

 

I like this discussion.   Keep it coming.   I'm building up the enthusiasm to attack my underbody. 

 

There is still original Inka paint and primer under the car, but there are areas of surface rust that I cannot accept.    Add in undercoating, grease and grime and the job just gets bigger and bigger.

 

My first thoughts are to clean and grind/wire wheel down to bare metal.    Follow that with an Eastman or Por-15 process and finish with an oil-base polyurethane.    I know, I know, oil-based polyurethane is not car paint but it's brushable and creates a thick resilient surface to largely unseen areas.    Did I mention it's Inka paint?

DSC02706sml.jpg

 

Interesting, once dried how close to Inka is it??  Did you have them mix it up for you or is it a stock paint??

 

TK

[PaulTWinterton]

I had it mixed at Lowe's. I took in a piece of my car and had them sample the color.  Came out very close. I would not use it on the outside of the car or adjacent original paint.   I'm sure that if the two colors were placed side by side under bright light there would be a difference, but eyeballing the 2 paints they look the same.  Strictly for underneath, trunk, and inside nose clip.

[jgerock]

What was your process for getting the original material off? Did you do it all from underneath while on jack stands?

Started from the back with the rear subframe out.  Putty knives, wire brushes, nylon brushes, a 3M stripper wheel and corded drill.  It made a mess.  I spread plastic sheeting down but my creeper wheels didn't roll very well so I just layed on my back.  I didn't take all of the factory applied stuff off - it was applied very well.  The biggest, messiest area was the driveshaft tunnel.  One of those rotisserie units or the cantilevered tippers would be a blessing while doing this job.   As seen in the pics, I did the back, installed the fresh subframe then did the front.  I used lots of paper to mask off the unwanted sections (and even the jack stands) because the Eastwood spray would go everywhere.  The flip down shield protected my face - I highly recommend getting one.  Use an old longsleeve shirt and wear disposable gloves.  I had bits of undercoating in my hair for a while.

 

Tip: use a coffee can lid over the round shifter opening on the early cars while power washing the underside.  I then put a piece of newspaper in the recessed area held down by an old CV joint while spraying the undercoating.

Edited September 18, 2015 by jgerock

[remout]

Started from the back with the rear subframe out.  Putty knives, wire brushes, nylon brushes, a 3M stripper wheel and corded drill.  It made a mess.  I spread plastic sheeting down but my creeper wheels didn't roll very well so I just layed on my back.  I didn't take all of the factory applied stuff off - it was applied very well.  The biggest, messiest area was the driveshaft tunnel.  One of those rotisserie units or the cantilevered tippers would be a blessing while doing this job.   As seen in the pics, I did the back, installed the fresh subframe then did the front.  I used lots of paper to mask off the unwanted sections (and even the jack stands) because the Eastwood spray would go everywhere.  The flip down shield protected my face - I highly recommend getting one.  Use an old longsleeve shirt and wear disposable gloves.  I had bits of undercoating in my hair for a while.

 

Tip: use a coffee can lid over the round shifter opening on the early cars while power washing the underside.  I then put a piece of newspaper in the recessed area held down by an old CV joint while spraying the undercoating.

 Oh, thanks for that ^.  We've got 3 to do and are debating on getting a Rotisserie.  

[PaulTWinterton]

Started from the back with the rear subframe out. Putty knives, wire brushes, nylon brushes, a 3M stripper wheel and corded drill. It made a mess. I spread plastic sheeting down but my creeper wheels didn't roll very well so I just layed on my back. I didn't take all of the factory applied stuff off - it was applied very well. The biggest, messiest area was the driveshaft tunnel. One of those rotisserie units or the cantilevered tippers would be a blessing while doing this job. As seen in the pics, I did the back, installed the fresh subframe then did the front. I used lots of paper to mask off the unwanted sections (and even the jack stands) because the Eastwood spray would go everywhere. The flip down shield protected my face - I highly recommend getting one. Use an old longsleeve shirt and wear disposable gloves. I had bits of undercoating in my hair for a while. Tip: use a coffee can lid over the round shifter opening on the early cars while power washing the underside. I then put a piece of newspaper in the recessed area held down by an old CV joint while spraying the undercoating.

 

Great!   Not sure if that gives me energy or kills my DIY inner child, but great knowledge none the less.  I'm more inclined to use the POR-15 brush on stuff rather than Eastwood spray.  Your thoughts?

[jgerock]

Great!   Not sure if that gives me energy or kills my DIY inner child, but great knowledge none the less.  I'm more inclined to use the POR-15 brush on stuff rather than Eastwood spray.  Your thoughts?

I took the easy way out and used the spray stuff.  On my VW, I cheaped out an bought the local auto parts rubberized undercoating.  Never again.  I tend to buy most of my auto supplies (paint and some of their tools) from Eastwoods.  They are in PA so quick delivery for me.

 

Have to be careful with the spray stuff.  One (full) can sprayed some yellow goop and I had to quickly wipe it off.  Must have been a preservative on the top.  The other cans didn't do this.

 

I've never used the POR products.  The PO of my tii used lots of it brushed all over the bottom (subframes, shocks, brake lines, etc) and now the paint on the rear subframe is peeling off.   I need to pull the front SF to reinforce the steering box mount - I'm dreading that.