Author Topic: Removing rust and protecting the underbody  (Read 5606 times)

Offline wally426ci

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Re: Removing rust and protecting the underbody
« Reply #15 on: December 01, 2009 - 10:45:21 AM »
Hey guys, I use POR metal Ready. Its about $32 a gallon. You spray, wipe, mop it on whatever and make sure it stays wet for at least 30 minutes. After that if the rust has started to convert, you hose it down good and then I hit it with etching primer.

I did this on the hood of my truck and it turned out great.

http://www.por15.com/METAL-READY/productinfo/MRG/
{OOI====I====IOO}
      '71 Challenger
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      '68 D100




Offline burdar

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Re: Removing rust and protecting the underbody
« Reply #16 on: December 01, 2009 - 02:02:13 PM »
EvapoRust is a liquid.  How are you going to brush it on and not have it Evapo-Rate away?  I've used it for small parts that I can dip but there are better products on the market that will accually stick to the bottom side of the car.

Hot Rod magazine did a big article on rust removing products this year.  Do a search for it.  They tested a rust removing gel that was designed to stick to body panels.  With the gel, it won't run off or evaporate so it has time to do the job.

To the OP...I know it has been awhile since you origonally posted this question but if you haven't started I really think I would just blast the underside and be done with it.

I used to work at an Exhaust Pros shop.  My boss was great at bending custom dual exhaust systems.  We did a few cars that were owned by a group of friends in town.  One was a 71 Olds 442 and the other was a mid 80's Firebird.  They put there cars up on stands and sand blasted the whole bottom.  THey painted the cars black underneith(which is probably how a GM product is supposed to be), rebuilt the suspension and rebuilt and repainted the engine/trans.  Those cars were soo clean under there.  The undersides really turned out nice.

You could blast the bottom of yours...spray it with a paint that looks like the factory primer and then duplicate the factory body color overspray. :2cents: 

Offline tommyg29

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Re: Removing rust and protecting the underbody
« Reply #17 on: December 01, 2009 - 02:12:43 PM »
burdar,
I havent started yet....Ive been following this thread and any suggestions. There are lots of products out there, and everyone has their opinions. Your suggestion is a good one, but I want to do it myself a small section at a time, and keep the car on the road, so I dont think media blasting will work for me.

Since you know something about tube bending, this is off topic, but how would you bend/dent headers to not knock against the steering box and the torsion bars?
Thanks.
72 Roadrunner 400-4 Auto-3.23 Gear-Black Cruiser
71 Cuda 440-6 Tribute-Limelight-A833 Close Ratio-4 Sp-Pistol Grip-Dana 3.54 Powr Lok-Rally Dash-Shaker (Sold)
92 Dodge Stealth RT-Twin 15g Turbos-SAFC2 Tuned-Mystic Blue-5 Sp-AWD-Rear Wheel Steering-AutoX'r (Sold)
12 Dodge Charger SXT Plus Blacktop Package-3.6L-8 Sp-Leather-Nav (the wife's)

Multiple SRT's, Rams, Dakotas, Caravans and Neons

...the lines on the road just look like dots!....

Offline burdar

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Re: Removing rust and protecting the underbody
« Reply #18 on: December 01, 2009 - 03:54:03 PM »
Some headers fit a lot better than others.  If it were mine, I'd find the best fitting header since I wouldn't be concerned with the small HP difference there might be between a bad fitting race header and a good fitting street header.  If you need to make some small adjustments, a large bar comes in very handy.  For clearencing shift linkage exc...I've used a torch and a hammer.  That doesn't leave your headers looking ver nice though.  I think it's best to get a more expensive set that accually fits.  The Tri-Y's seem to fit pretty good but don't produce the most hp.

Offline tommyg29

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Re: Removing rust and protecting the underbody
« Reply #19 on: December 01, 2009 - 05:16:57 PM »
The blue gel product Hot Rod liked was called Rust Bomb. I'm gonna try to check it out some more. Also need to further research the cleaning and rust inhibiting followup coatings.

As for the headers I was actually considering denting my Hooker super comps til they fit as good as I can get em, then remove them and have em coated. Though I'm afraid the removing and reinstalling might be a little much for me, without a lift, etc.
This way also solves the problem of getting the new header collectors to match up with my 3" TTI exhaust.
72 Roadrunner 400-4 Auto-3.23 Gear-Black Cruiser
71 Cuda 440-6 Tribute-Limelight-A833 Close Ratio-4 Sp-Pistol Grip-Dana 3.54 Powr Lok-Rally Dash-Shaker (Sold)
92 Dodge Stealth RT-Twin 15g Turbos-SAFC2 Tuned-Mystic Blue-5 Sp-AWD-Rear Wheel Steering-AutoX'r (Sold)
12 Dodge Charger SXT Plus Blacktop Package-3.6L-8 Sp-Leather-Nav (the wife's)

Multiple SRT's, Rams, Dakotas, Caravans and Neons

...the lines on the road just look like dots!....

Offline dodj

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Re: Removing rust and protecting the underbody
« Reply #20 on: December 01, 2009 - 08:31:00 PM »
It looks like Rust bomb is gelatinous Evapo-rust. I think I'll order some of that too. I used the evapo-rust this afternoon on a section of frame and it does work well, just drippy. It doesn't evaporate very fast so I just sprayed a little bit more every 15 minutes or so, scrapped a bit, repeat. The gel would be less messy and you wouldn't have to tend it as much I guess. :2cents:
Scott
1973 Challenger  440 4 spd 
2007.5 3500 6.7 Cummins Diesel, Anarchy tuned.
Good friends don't let friends do stupid things. ........alone.

Offline dodj

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Re: Removing rust and protecting the underbody
« Reply #21 on: December 02, 2009 - 06:01:14 PM »
Guess I can't buy Rust Bomb. I sent them an email about ordering some and was given this reply.

'Thank you for your inquiry.  We do not make the rust bomb any longer.  We are re-formulating and hope to have a new product out in the spring.  Rust Bomb was a great product, but the shelf life was shorter than we had desired.'


Scott
1973 Challenger  440 4 spd 
2007.5 3500 6.7 Cummins Diesel, Anarchy tuned.
Good friends don't let friends do stupid things. ........alone.

Offline ambitions2

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Re: Removing rust and protecting the underbody
« Reply #22 on: December 10, 2009 - 11:27:03 AM »
My 2 cents

- You want to keep it on the road
- You want to do a small section at a time

I would probably go this route, break the car up into 3 sections - rear, middle and front

Starting with the back I would put the car up on jacks and remove the drive shaft, rear end, leafs, gas tank, etc. and work on it from the rear floors and back.  I would then remove the rust (I did the heat and scrapper in the wheelwells and then wire-wheeled the rest on the bottom on my '72...cheap and very effective.  When I brought it to the blaster the guy was amazed on how clean it was). 

We used the POR15 for the bottom of 2 cars - just have to wipe down the bottom with their solution (least we did).  Came out great.

Repeat the process for each section


I would assume a weekend + 3 or 4 days where the car can't be drove. 
Project: 1972 Challenger - 340 AT 8 3/4 3.23 gears
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Offline tommyg29

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Re: Removing rust and protecting the underbody
« Reply #23 on: December 10, 2009 - 04:24:24 PM »
ambitions,
excellent suggestions. I want to keep it on the road as much as possible, but I cant remove the rear end. On the rear, I will remove the tank and driveshaft...easy enough...and then get to cleaning and coating whatever I can reach.
72 Roadrunner 400-4 Auto-3.23 Gear-Black Cruiser
71 Cuda 440-6 Tribute-Limelight-A833 Close Ratio-4 Sp-Pistol Grip-Dana 3.54 Powr Lok-Rally Dash-Shaker (Sold)
92 Dodge Stealth RT-Twin 15g Turbos-SAFC2 Tuned-Mystic Blue-5 Sp-AWD-Rear Wheel Steering-AutoX'r (Sold)
12 Dodge Charger SXT Plus Blacktop Package-3.6L-8 Sp-Leather-Nav (the wife's)

Multiple SRT's, Rams, Dakotas, Caravans and Neons

...the lines on the road just look like dots!....