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Rust inhibitors/preventatives

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Neemer

Crayon Eater
RVF Supporter
Joined
Dec 27, 2019
Messages
1,913
Location
Virginia
RV Year
2021
RV Make
Newmar
RV Model
DSDP 4326
RV Length
43
Chassis
Freightliner
Engine
ISL 450
TOW/TOAD
2023 Winnebago ERA 70A or 2012 Ford Taurus
Anyone using a rust inhibitor on exposed chassis parts? I’m looking at either POR-15 or Fluid Film. Anyone have seasoned advice to pass along?
 
I am actually very involved in a project related to my winter delivery, and the "prevention" that I will be doing. I am not sure if this is what you are after, or if you are speaking more in terms of general "rust". My goal is more around winter salts and chemicals, and the corrosion it does to the RV, etc.

Can you elaborate a bit on what you are after?
 
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We spend a fair amount of time in areas around saltwater, and our winter migration once resulted in driving in snow and on treated surfaces around Flagstaff. I want to prevent those factors from getting a toe hold in our new coach. My old KSDP had a lot of surface rust on frame members and just about every exposed metal part.
 
POR-15 is a fantastic product as long as you follow the manufacturers procedures. It is not something that you would want to apply over large and tough to access places. Fluid film is more along the lines that I think you are looking for. It is a natural oil that helps prevent the negative affects of road salt etc. easy to apply with most any type of sprayer without surface prep. The negative is that it doesn’t last too long. I have used it and it certainly works but in New England I need to apply it twice to maintain protection.
 
This is what I do. Take it for what it is, and keep in mind that I am very particular about the rust, so this is probably overkill for most people.

But -- since you asked :)


Assumption is a clean vehicle, without rust. If you have rust, you must take corrective action and then come back to these steps. My process will not do anything to treat existing rust. It is also assumed that the metal is not a raw metal, and that it has at least some form of paint coating on it. Raw metal will require a constant coating of grease.

For under body / chassis / engine / hinges I use a gallon size garden sprayer and coat every square inch with this product:



You do not want this to get into your air intake, your alternator coils, or any electrical connections.

All electrical connectors are treated with Dielectric grease around the housings prior to applying this product underneath. The alternator I tape up really well.

You want to spray a very wet coating, and allow it to dry. Spend time to make sure it is applied at all angles. When doing this to a motor home, a long wand will help. You want to focus around the engine from all angles, and be extra liberal around the exposed c channels. This is a good time to plug up any unnecessary holes with a good rubber compound.

It is OK to get it on the exhaust system, but don't waste product here, as it will burn off.

It is OK to get on the brake calipers and discs, but again, don't waste product here--if it gets some over spray, that's fine. It will be burned off when braking, so don't waste product there.

Slide out the generator, and get the rails on both sides, as well as the generator housing. (Make sure you apply liberal amounts of Dielectric grease to the electrical connections before you spray).

Find any and all exposed metal on the front cap, including windshield wiper arms, arms, mirrors, etc. and coat these too. Having a spray bottle helps for these areas.

Open the battery tray. Use plenty of Dielectric grease on top of all connectors, and liberally spray the "Classy Chassis" on all metal parts of the tray, and frame rails exposed.

Get under the RV and spray everything. ( I am repeating for emphasis)

Open the Bay doors, and spray the hinges and latches, as well as the exposed frame rails. I use a spray bottle for this area.


That is round #1.

By the time you have finished, the first part you did should be dry.

You need 3 coats. DO NOT SKIMP.


Classy Chassis is going to do several things:

#1 - It is going to attach itself to the metal. It will move dirt and other pollutants out of its way, moving it to the surface. It will not move rust, but it will move grease, caked on dirt, etc.

This is why you start with a clean surface. You don't want to use up the product to do the cleaning for you.

#2 - It is a barrier against anything attaching to the surface. Once dry you can test spray painting it, you will find that the paint does not attach (tested on small test area). Salt and other chemicals do the same. Water will not remove this product.

The product can become overwhelmed with dirt removal, and eventually is no longer effective. That is why we are doing 3 coats. 3 coats will last for several months of nasty weather driving. My daughter lives in Chicago area, and we treat her jeep in November, and clean up in March, and its perfect.


To remove the product, I use an all purpose cleaner from Shine Supply mixed at 4:1 (Solution - Gallon)


BTW---Solution is the best cleaner. I will talk more about that later.


For an RV -- you want 4 gallons of Classy Chassis. You will have plenty to treat your toad too. This will last one season...or if you are really picky, One trip in the winter driving conditions.
 
That’s a lot of work. Why not just take out the pressure washer and give the undercarriage a good rinse to get the salt off.
 
That’s a lot of work. Why not just take out the pressure washer and give the undercarriage a good rinse to get the salt off.

That is what 99.9% of people do.

That is the procedure that Newmar says to do with new deliveries.

Most people will be happy with that.

BUT--why do I go further?

Imagine driving in wet weather for 100 miles. This slop of melted ice and snow is mixed with the chemical (salt or whatever) that was responsible for making it wet. The amount of time it takes to drive 100 miles is several hours. During that time, water not only touched the surface, but crept into nooks and crannies. It "walked the line" into all areas and angles exposed.

The corrosive chemical started eating right away. That is a chemical process that is instant. The process does not end with just water, but lets assume for a moment it does.

You would have to spray enough water to cover every inch, and remove it from the metal. This would take a long time. In 2013, I used a couple of garden sprinkler attachments on a hose, and left it bathing under the coach, engine bay, and front end for 4 hours. I began the process within 15 hours of first contact.

What I should have done is followed up with a neutralizer. Newmar does not do this, dealers do not do this, and it is an absolute necessity.

Within 1 year, I had rust showing all over the engine, the accessories, and my doors where all very hard to operate.

The repair procedure was extensive. Newmar covered the engine rust, and door hardware. The accessories never where addressed. (pullies on water pump, alternator, etc). The coach spent 5 days in the body shop, and 10 days in the repair facility to address all of the corrosion. This was from a single trip from Nappanee to Texas.

in 2015, I had to again take the coach to newmar in winter conditions. By that time I had learned about the neutralizers. I did the same procedure as I had done before, but started with a heavy coating of a neutralizer. I then finished with a neutralizer spray.

I never had any rust issues.

The procedure I outlined above is a way to prevent the chemicals from making contact with the metal, and thus eliminates the need for the neutralizer. The neutralizer is difficult to spray (same as my procedure), and by design, is doing so *after* the fact.

Now that I know the difference, I have a plan of prevention that I put into place so that I don't need to exercise the plan of correction.
 
BTW--neutralizer is cheap. Its just two tablespoons of baking soda in a gallon of water. Spray on with the same methods, and then use pressure washer to remove the residue.
 
I want too see the underbelly of your current coach now.
 
I want too see the underbelly of your current coach now.
Sadly..I don't have a coach at the moment...I keep selling them.
 

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