Undercarriage Rust Management

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Hey guys.

So my Buick Regal is now "salvage" after a moderate bump by a truck slightly buckled a quarter-panel. So naturally, I kept the car, since like half the purpose of this (my first) car has been to DIY what I can and learn how to do things myself and when to know when to leave it to the pros.

So as much as I have been under my car, I've noticed it is fairly rusty. I thought this was a fairly normal thing, but apparently it is something that needs to be tackled. The original muffler exploded during the test drive, apparently due to rust. So I replaced that right away with a larger pipe and Magnaflow. The brake line also broke from rust, so my dad and I worked on replacing the whole line (it works very well now!). The drive axles are fairly rusty, though mostly surface.

So what products and methods do you guys recommend for cleaning rust and sealing FROM rust? I've seen where people just spray some rustoleum on the rusty parts, but I figured there would be more to it than that. A good cleaning at the very least.
 
Some options:
POR15
Wire wheel or sandblast, prime and paint
oil spray
Krown
Fluid Film

I like fluid film as it very easy to apply and pretty effective- not perfect though.
 
pressure wash it every spring to remove the salt and brine. Use garden hose to get in the pockets too. Then paint it with black spray paint...careful of overspray and your eyes, hands, nose.
 
Paint what you can right over the rust, then spray your used oil with a garden sprayer thereafter. I'm not convinced the quality of the paint matters that much. 2 dollar rattle can primer adheres just as long as POR.

Cut your used motor oil with diesel to make it more sprayable. I'm trying to work out putting a 90 degree fitting on my garden sprayer wand so I can just pass it under the car without jacking.

Bottom line. Oil the heck out of it. Areas of my 40 year old cars that look perfect are where there was a steady drip from the engine and tranny. If my trans am hadnt had a wicked leaky rear tranny seal, it would be beer cans by now.
 
If you already have a way of getting the car in the air, then all you'll need is a drill with a wire brush attatchment to get down to bare metal.
One you can see bare metall, paint generously with Waxoyl. It will NOT rust after you do that..
 
When I started driving/maintaining my own vehicle in the 70's, it was standard to let them rust and then complain about it.

It does not have to be that way.
My 2002/134,000 miles Ford Ranger has no rust yet.

My solution has been to get the underside sprayed with an undercoating oil.

Suggestions:

1) Have it done professionally the first time (check Yellow Pages and ask around).
They will spray in the doors, hood, trunk, brake & gas lines etc.
This will cost around $100.00 and will be the most effective and time saving way to go.
The oil will penetrate the rust and work its way to the base metal resulting in no further rusting. The oil will also work its way around the spot welds and in seams.

2) Buy Fluid Film in Aerosol cans and a 1 gallon can and use it for touch up work in the Fall.
I buy Fluid Film (aerosol) from E-Bay sellers (12 cans/1 case).
The 1 gallon can lasts along time.

3) Any future vehicle you own, get it oil sprayed right away and you may never have rust problems again.

4) Right or wrong, I've been coating my brake lines with Never-Seize (aluminum) and to this day, if I wipe it off, the brake lines look brand new.

I wish someone explained all this to me years ago instead of learning the hard way.
Good luck.

DO NOT BE TEMPTED TO USE MOTOR OIL FOR UNDERCOATING. IT'S THE WRONG CHOICE IN MANY WAYS
Edit: Fluid Film will not harm any rubber components, or electrical wiring, used motor oil will.
Fluid Film is Lanolin base (oil from sheep wool).
 
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I would suggest Krown or Carwell. Either of those will penetrate the rust and block future rust. Wire brushing/sanding and then prime and paint is fine for easy to access flat areas, but the undercarriage of a vehicle has many areas that will not be easy to wire brush/sand.

You can order CSarWell by the gallon. It can be sprayed or brushed on.

FluidFilm is similar to CarWell, but does not last quite as long.

Don't forget to look at the pinch seams of the doors for rust.
 
Originally Posted By: larryinnewyork
When I started driving/maintaining my own vehicle in the 70's, it was standard to let them rust and then complain about it.

It does not have to be that way.
My 2002/134,000 miles Ford Ranger has no rust yet.

My solution has been to get the underside sprayed with an undercoating oil.

Suggestions:

1) Have it done professionally the first time (check Yellow Pages and ask around).
They will spray in the doors, hood, trunk, brake & gas lines etc.
This will cost around $100.00 and will be the most effective and time saving way to go.
The oil will penetrate the rust and work its way to the base metal resulting in no further rusting. The oil will also work its way around the spot welds and in seams.

2) Buy Fluid Film in Aerosol cans and a 1 gallon can and use it for touch up work in the Fall.
I buy Fluid Film (aerosol) from E-Bay sellers (12 cans/1 case).
The 1 gallon can lasts along time.

3) Any future vehicle you own, get it oil sprayed right away and you may never have rust problems again.

4) Right or wrong, I've been coating my brake lines with Never-Seize (aluminum) and to this day, if I wipe it off, the brake lines look brand new.

I wish someone explained all this to me years ago instead of learning the hard way.
Good luck.

DO NOT BE TEMPTED TO USE MOTOR OIL FOR UNDERCOATING. IT'S THE WRONG CHOICE IN MANY WAYS
Edit: Fluid Film will not harm any rubber components, or electrical wiring, used motor oil will.
Fluid Film is Lanolin base (oil from sheep wool).


I agree, get it done by a shop the first time (watch) and don't use used motor oil as the product.
 
Originally Posted By: turtlevette
Paint what you can right over the rust, then spray your used oil with a garden sprayer thereafter. I'm not convinced the quality of the paint matters that much. 2 dollar rattle can primer adheres just as long as POR.

Cut your used motor oil with diesel to make it more sprayable. I'm trying to work out putting a 90 degree fitting on my garden sprayer wand so I can just pass it under the car without jacking.

Bottom line. Oil the heck out of it. Areas of my 40 year old cars that look perfect are where there was a steady drip from the engine and tranny. If my trans am hadnt had a wicked leaky rear tranny seal, it would be beer cans by now.



People should be properly disposing of used motor oil not spraying it on the undercarriage of their vehicle. Imagine what a mess our environment would be if when you went to Jiffy Lube, then changed your oil and filter and then sprayed the used motor oil on your vehicle's undercarriage and you drove off dripping motor oil all over for the next 500 miles.
 
Used motor oil is teratogenic and carcinogenic.

Unused motor oil isn't, and a little goes a very long way.

I use a blend of motor oil, diesel and sunflower oil. Fluid Film MAY be much better but you can't get it here.

I've used Waxoyl (which is probably similar, and which you can't get here either) a LONG time ago and didn't think much of it.

In context its quite important that you use something that's easy (and preferably cheap) to use, else you wont use it.
 
Originally Posted By: Ducked
Used motor oil is teratogenic and carcinogenic.

.


Its not on your skin. Its under the car. Exhaust is extremely deadly, but your face is not 6" from the exhaust. The asphalt roads are very toxic too. Brake dust is toxic. Rubber particles cause cancer. People think a few drops of oil is so horrible.



Motor oil does stink though. Use your used frying oil instead.
 
Originally Posted By: Need4racin
pressure wash it every spring to remove the salt and brine.


^Do not do this.

Pressure washing on an intact (i.e. non rusty) vehicle will result in you blowing off all the anti rust coatings that protect the underside. Use a garden hose, you do not need 1500ft/lb of pressure to wash away salt.

In a car as old and deteriorated as yours, if there's no structural rust...look around the joints where suspension parts meet the under body...then a one step rust block/sealer is your best bet. Get under other with a stiff metal brush to remove as much rust as possible.

But like most advanced cancers, once rust takes a firm hold on your car, the goal is palliative rather than restorative.
 
Corrosion X is another amazing product - I use both the thin penetrating version and the thick and sticky undercoating version - effective, even on my boat trailer springs that get dunked in salt water regularly.
 
Originally Posted By: Noey
Originally Posted By: Need4racin
pressure wash it every spring to remove the salt and brine.


^Do not do this.

Pressure washing on an intact (i.e. non rusty) vehicle will result in you blowing off all the anti rust coatings that protect the underside. Use a garden hose, you do not need 1500ft/lb of pressure to wash away salt.

In a car as old and deteriorated as yours, if there's no structural rust...look around the joints where suspension parts meet the under body...then a one step rust block/sealer is your best bet. Get under other with a stiff metal brush to remove as much rust as possible.

But like most advanced cancers, once rust takes a firm hold on your car, the goal is palliative rather than restorative.


Would think that pressure would be bad for any wire harness. Also would a clean undercarriage be more likely to rust because there is a better supply of oxygen to exposed or rusting metal?
 
Hey guys.

So my Buick Regal is now "salvage" after a moderate bump by a truck slightly buckled a quarter-panel. So naturally, I kept the car, since like half the purpose of this (my first) car has been to DIY what I can and learn how to do things myself and when to know when to leave it to the pros.

This sounds like something a Father would say.

Once I found this web-site, I take better care of my vehicle.
I change ALL the fluids, which has to go a long way in 'preventive' maintenance.

Small to medium Repairs - Get advise here from others. Even if it's just to confirm your common sense.
You-Tube is also very good.

And about the oil-undercoating: I'm always wiping the oil off the doors and tailgate because it 'creeps'. That's what you want in an undercoating oil.
 
Originally Posted By: turtlevette
Originally Posted By: Ducked
Used motor oil is teratogenic and carcinogenic.

.


Its not on your skin.



It will be.

Depending on how used it is, it may also be acidic, which tends to defeat the object. Rinsing out your nominally empty oil bottles with a bit of diesel (or kerosene, which is nicer) you get unused oil essentially for free. The saving with used oil is negligable and doesn't justify the downside.
 
Originally Posted By: turtlevette
Originally Posted By: Ducked
Used motor oil is teratogenic and carcinogenic.

.



Motor oil does stink though. Use your used frying oil instead.


Used frying oil used alone isn't toxic like used motor oil, but its quite likely to grow mould in enclosed spaces. This might not be much of a problem outside the car (say in box sections), but inside, say, the door skins, its a potential respiratory hazard.

I think this risk is reduced by using fresh oil and blending it with motor oil and diesel, but it isn't entirely eliminated. Safer to just use mineral oil in those locations.
 
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Re fluid film being lanolin based...lanolin is expensive as all get out, I use it in my gun lubes.

http://www.fluid-film.com/downloads/SDS_Aerosol.pdf

Seems like a rust inhibiting grease carried by oil...lanolin may be in there (not listed in the MSDS), and a tiny bit makes it smell nice, but it's not "lanolin based".

Honestly, I can't see an annual spray underneath with used engine oil is going to be that environmentally devastating.

I wouldn't do it, have no need, but risks are tiny to both the weekend applicator and the environment.
 
A friend swears by "hot oil undercoating" which he gets in Vermont. I don't know what is in the mix. They do drill small holes and squirt using long extensions. They finish off with red plugs.

I keep meaning to go by there and see the place. I saw his truck immediately after the application and the gooeyness was everywhere. Now, a year later, the truck seems normal.
 
Originally Posted By: Shannow
Re fluid film being lanolin based...lanolin is expensive as all get out, I use it in my gun lubes.

http://www.fluid-film.com/downloads/SDS_Aerosol.pdf

Seems like a rust inhibiting grease carried by oil...lanolin may be in there (not listed in the MSDS), and a tiny bit makes it smell nice, but it's not "lanolin based".



Probably depends on the grade. If its crude lanolin, from the early stages of wool processing, (and I can't see why you would need anything more refined), its hard to see why it would be expensive, at least not in sheep country.

Sheep are rare and, weirdly, a tourist attraction here, so crude lanolin might be hard to find.

You're in Australia, though. You could probably just drive your Land Cruiser through a recently used sheep dip. Stop it getting all sorts of parasites.

Originally Posted By: Shannow


Honestly, I can't see an annual spray underneath with used engine oil is going to be that environmentally devastating.

I wouldn't do it, have no need, but risks are tiny to both the weekend applicator and the environment.



Sure, but the certainly tiny saving doesn't justify the probably tiny risks.

You're going to spray this stuff, so wind drift is probably going to put some of it in your face, and your probably leaky sprayer is probably going to put some of it on your hands.

Then you'll probably get some of it on you every time you go under the car. Diesel is quite unpleasant enough.
 
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