Underbody Rust Proofing DIY

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Originally Posted By: Donald
The shop typically has more experience with various vehicles and where the body cavities are that need spraying. They also have long wands (2' maybe 3') to get into the body cavities.

I would look for CarWell or Krown and if neither then Fluid Film. Even if your plan is DIY get it done once for $100 and watch.

The shops also give new vehicle warranties.


We have a winner!!

How right you are.
 
Originally Posted By: demarpaint
Originally Posted By: jcwit
Originally Posted By: demarpaint


And then there are those of us who can do a better job themselves, or don't have a shop anywhere near them that does rustproofing.


Doesn't mean every ding dong out there knows what they're doing!

I know how to tear an engine down and rebuild it, doesn't mean my neighbor knows how!


I never said every ding dong knows what they're doing. That's why we hear about oil changes a simple task being screwed up by so called pros! There are good and bad mechanics in all walks of life. Rustproofing a car is not rebuilding an engine. Anyone mechanically inclined,who is physically able, and has the desire to do it, can. If you don't know how to do it you ask. To make is sound like an impossible task for only a professional is wrong.


Never said it was impossible, but for the person not knowing what he's doing it's not a case of just spraying snot out of a gun pointing it where ever.
 
That's why I go to Krown for the first treatment so that they can drill all the holes for me. I may go once more to get some thickness inside the doors etc, but after that I'm DIY-ing. If I was not touching up extra areas on my 06 Mazda 3, it would be showing rust now even with the "pro" Krown treatment. YMMV.
 
For your reading pleasure.

http://www.howtosavemoney.ca/which-rust-proofing-service-is-best

Part of the article

What Rust Protection Is Best?

These are the typical choices you have for brand name rust proofing:

Rust Check
Krown
Corrosion Free
Plus, a few other products that you can only apply yourself (not recommended).

There have been several tests run by the Canadian Army on which rust proofing product provides the best protection. You can read the 2006 report here and this post at RedFlagDeals summarizes the results nicely.
The Best Protection

The clear winner in the army tests is Corrosion Free! They found that Corrosion Free was more than 90% effective at inhibiting rust even in the harshest climates. The next closest product was only 70% effective and to my great horror Rust Check was rated at under 40% effective.

That’s what I get for being brand loyal all these years without doing my research! Rust Check definitely works, but I could have been doing so much better all along had I known.
The Best Warranty

The warranty by Rust Check and Krown only covers rust originating from the inside of metal panels and excludes floorboards and sometimes roof panels. They also require an actual hole in the vehicle before they will honour the warranty. Corrosion Free is the only one to cover all body panels and have no restrictions on where the rust originates from. They also don’t necessarily require a full hole before getting it fixed for you. You can read their full warranty sheet here.
Application Interval

Rust Check and Krown require reapplication every 12 months to keep your warranty valid, whereas it is 18 months with Corrosion Free. Less appointments and less hassle, sounds good to me.
 
Bacon grease

Smells great when accidentally sprayed on the exhaust
thumbsup2.gif

It's also biodegradeable and you don't have to worry about any harmful fumes/contaminants
It's also free/close to it, and can be obtained at almost any truck stop/diner
 
If you DIY, you need to spend time learning: which material/tools/techniques and identify all the hidden pockets, etc.. If you pay a pro shop, you need to be your own advocate to ensure that they do a thorough job (most shops have low paid techs.). Both ways can produce poor results.

That Canadian Army research is a starting point, but the test methods do not duplicate vehicle conditions. Unfortunately, Canadian Tire is the major vendor for Corrosion Free and there are many complaints of poor application by their shops. The Corrosion Free dealer in Ann Arbor Michigan is VERY expensive, something to the tune of $300+ per application when I inquired.

There are no silver bullets. Vehicles are wear items and life is too short to obsess about them IMO. Do a reasonable job of trying to maintain them and count on having to replace them when needed.

If I were to DIY this, I would consider something better than Fluid Film.....Demarpaint and Trav make some good suggestions. I'm having my current vehicle Krowned annually for $125 plus driving expense. Not cheap. Cost effective?? Time will tell, but probably not. Its a feel good thing for me and where part of my discretionary money ends up.
 
Originally Posted By: jcwit


The clear winner in the army tests is Corrosion Free! They found that Corrosion Free was more than 90% effective at inhibiting rust even in the harshest climates. The next closest product was only 70% effective and to my great horror Rust Check was rated at under 40% effective.



I'm on my second application of CF 3000 which was applied Oct 2015. I powersprayed the underbody on the weekend, and the water still beads up nicely.

Having said that, cans of CF 3000 were on sale at the TSC store last week for $5.00 each, so I bought two cans to do some touch-ups before winters comes. Despite the fabulous weather we've had, winter is coming
cry.gif
 
Appreciate the feedback guys. Closest place would be 50 miles away for $399. If I could find the service for $100 I would undoubtedly fork the cash over and keep up on it.
 
I have a body shop here in central No. Indiana that applies Corrosion Free. They power spray the under body the day before application. The gentleman who does the application has been with the dealer for 10 years as of last year, so I'm more than sure he does know what's doing, plus after all these years of the body shop being in business and employing 10 tech's he "the owner" has a reputation to uphold.

I will say that I do do a "retarded monkey" spray of snot consisting of a combo of bar & chain oil and Fluid Film before winter sets in, it's just for the floor pan tho, far from being the entire car.
 
Originally Posted By: jdirtrider
Appreciate the feedback guys. Closest place would be 50 miles away for $399. If I could find the service for $100 I would undoubtedly fork the cash over and keep up on it.


$399 sounds about right if they're going to spend some time and use a good product. When I hear $100 I'm programmed to think Long Island prices. Around here for $100 you can't even buy an hour labor from a pro, let alone the material. So for $100 how much time do you think they're going to spend, [anywhere in the US], and how much material will they apply? Is the material any good at that price? I'll do it myself and know it was done right and with a good product. No different for me than a DIY oil change, tune up, or brake job. Then I have the satisfaction of knowing it was done right and I saved money. Different strokes for different folks I guess.

As far as the warranty, it's probably just like an oil company's warranty. Not worth the paper it's written on, with lots of fine print and loopholes.
 
I had my 2002 Ford Ranger 'oil' undercoated at a nearby shop for 5 years.
I have so much of that 'oil' under there now, I just touch-up spots that are lacking.

What I also did: Coated my Brake Lines with Never-Seize thinned out with a little Fluid Film.
I live in the rust-belt and after 14 years, my Brake Lines still look brand new.
I feel the Brake Lines need some special attention using a product that will NOT wash off.

Warning: Do not use Used Motor Oil.
Fluid Film will not harm Rubber Components or Electrical Wiring & Outlets.
 
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The shop typically has more experience with various vehicles and where the body cavities are that need spraying. They also have long wands (2' maybe 3') to get into the body cavities.

I would look for CarWell or Krown and if neither then Fluid Film. Even if your plan is DIY get it done once for $100 and watch.

The shops also give new vehicle warranties.
 
Originally Posted By: larryinnewyork
I had my 2002 Ford Ranger 'oil' undercoated at a nearby shop for 5 years.
I have so much of that 'oil' under there now, I just touch-up spots that are lacking.

What I also did: Coated my Brake Lines with Never-Seize thinned out with a little Fluid Film.
I live in the rust-belt and after 14 years, my Brake Lines still look brand new.
I feel the Brake Lines need some special attention using a product that will NOT wash off.

Warning: Do not use Used Motor Oil.
Fluid Film will not harm Rubber Components or Electrical Wiring & Outlets.


I wish the auto mfg's used a copper/nickle brake lines. Little more expensive but you never need to worry about corrosion, at least in my experience.
 
Originally Posted By: jcwit
I have an 8 year old car that has not one spec of rust on it, the same with my 11 year daily driver, and I live in the rust belt!


I dare you to remove all the interior panels for the doors and in the wheel wells and inspect for rust.


My 97 civic had no rust on it until a couple of years ago. I've had it rust proofed professionally for the past
7 years. Last year I was ticked to find out that they didn't drill all the way through the rear panels to apply the rust It was bone
dry.

I picked up the fluid film and gun last year and did it myself. A lot of these places know most people won't keep vehiclestwhat for ever, so I'm sure some of them skimp on what they spray.

Originally Posted By: Trav
Much of the time someone who never did the job will do it more thoroughly than a bored "pro". As DP said its not rocket science.


Thanks Trav, I agree.
 
Well all the door panels were removed last year to replace springs that could break, they were replaced with U.S. springs in the hopes they would not break. Yes the doors were all coated as they should have been. My local body man who's shop is 1/2 a block from me claimed that my rust proofing job was top notch.

With all that said the oil is still creeping from out of the doors of both cars and from the fenders and the rocker panels. Both cars go in next spring for reapplication.

I do know for a fact the fire wall and behind the headlights and radiator mounts are all rustproofed.

What more do you think I should do, at 73 I'm not going to remove the plastic from the fenders, being as I can see the the oil is still creeping at this time.
 
Originally Posted By: JC1



Originally Posted By: Trav
Much of the time someone who never did the job will do it more thoroughly than a bored "pro". As DP said its not rocket science.


Thanks Trav, I agree.


Like I said earlier the dealer I use to apply Corrosion Free has been in business for way over 10 years, his employee who does the application has been with him for 10 years and the dealer has a reputation to uphold. His BBB rating is A+.

Granted it's not rocket science, but it does take someone who knows what they are doing. You are correct in the fact we are not going into outer space!

For those of you who wish to DIY, go for it, GOOD LUCK!
 
Generally speaking, if something is too much trouble to do properly yourself, its far, far too much trouble to get it done properly by anyone else.

Here its probably not even an option, so DIY/home remedies are all there is.
 
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Originally Posted By: jdirtrider
Appreciate the feedback guys. Closest place would be 50 miles away for $399. If I could find the service for $100 I would undoubtedly fork the cash over and keep up on it.


What product would they be using?

In my part of the country, no places do oil undercoating. The only place that does it sprays some kind of wax and then covers it all with rubberized undercoating. They want more than $400 for that job and I definitely don't want something that includes a rubberized spray as part of the job.

Fluid Film works well, is affordable, easy to buy and easy to apply. It will wash off over time in high-spray areas like wheel wells, but from my experience it doesn't wash off that fast and still offers a lot of protection.

My experience has been that FF does not really wash off of other areas like frames very easily. My suggestion for an easy DIY would be a thorough FF treatment and a spot touchup every year on the high-wash areas.

I've ordered FF online in the past, but I recently found out you can get it through NAPA for a better price.
https://www.napaonline.com/napa/en/p/FFQCNAS/FFQCNAS

You can also spray FF with airless paint sprayers if you don't have a large air compressor.
 
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