Brake fluid as penetrating oil.

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Has anyone ever tried using brake fluid as a penetrating oil? My experience has been very successful with dismounting old tires. I have my own bead breaker and usually mount my own tires, (I have a balancer as well and balance my own tires). Occasionally, especially when working on old farm machinery, I'll get a tire that is rusted onto the wheel making it very difficult if not impossible to break the bead. What I'll do is lay the tire on it's side and pour a small amount of brake fluid around the bead and let it sit for a few days. Then I'll flip the tire and do the same on the other side. The bead will then break with practically no trouble at all and very little effort. While I know this works as I have done it for years, I don't know why it works. Does anyone have any idea why brake fluid works so well when other things, (old oil, diesel fuel, WD-40) won't even touch it?
 
Yes they do make decent penetrants because brake fluid (a special hydraulic fluid) is composed of esters and corrosion inhibitors that provide a good surfactant.

Brake fluids are blends of several components such as vegetable oils, various alcohol-based fluids, and synthetic ester base oils, diluents and one or more oxidation and corrosion inhibitors.

Mix it 50/50 with a synthetic ATF like DexronVI and you have yourself a general purpose penetrating fluid.
 
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Cool
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Originally Posted By: MolaKule
Yes they do make decent penetrants because brake fluid (a special hydraulic fluid) is composed of esters and corrosion inhibitors that provide a good surfactant.

Brake fluids are blends of several components such as vegetable oils, various alcohol-based fluids, and synthetic ester base oils, diluents and one or more oxidation and corrosion inhibitors.

Mix it 50/50 with a synthetic ATF like DexronVI and you have yourself a general purpose penetrating fluid.


+1
 
Call me a crazy, paranoid lunatic, but I'm deathly afraid of brake fluid. I like the paint on my cars, tool boxes and shelves too much to be slinging that stuff around anywhere but into a master cylinder.
 
Originally Posted By: tightwad
Call me a crazy, paranoid lunatic, but I'm deathly afraid of brake fluid. I like the paint on my cars, tool boxes and shelves too much to be slinging that stuff around anywhere but into a master cylinder.

Me too. The only place I use brake fluid is in the brake system, nowhere else.
 
I have heard a lot of people swear by this as a mixture. 50/50 atf to used brake fluid. I have about 2 gallons of used brake fluid I plan to mix up with ATF (from an upcoming trans flush) and keep it for a penetrating oil. Supposedly this mix works better than 90% of the off the shelf stuff, and its basically free if you use your used fluids to mix it up. Flushing brake system every other year is a good maintenance habit to have, and a qt of ATF makes for a lot of penetrating oil.
 
This is interesting. I hate brake fluid with a vengeance. Always flaring a still-dripping line, on my back, with fluid running up (down?) my arms, with the car on jackstands and no space to flinch.

I wouldn't voluntarily use it for anything else.
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When I get a stubborn bead I put the tire/wheel on the ground then use an OE scissors jack (with the 4x3 inch bottom) braced between the tire and frame of my heaviest vehicle. Crank away and it gets that bead loose, every time.
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50/50 ATF and Acetone mix.

Brake fluid is harmful to paint, best to not get too comfortable with the stuff. Will pull the black tar paint off of a driveway and leave an ugly brown spot.

If you want to be safe around a car I only trust ZEP 45.

Starting to get more comfortable with Liquid Wrench.

I only trust WD-40 to clean out a lock, worked for me for years to keep locks from freezing (we get a lot of freezing rain in Montreal).

I only trust Fluid Film to protect the car from salt rot. Everything else can rot out rubber boots (links, ball joints, rod ends etc..)
 
Originally Posted By: Falken
I only trust WD-40 to clean out a lock, worked for me for years to keep locks from freezing (we get a lot of freezing rain in Montreal).

It is a good cleaning agent. Works well as a Goo-Gone replacement for cleaning adhesive/tape residue.
 
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ATF and brake-fluid don't mix (ATF floats) so I'm not sure how effective this mix really is. Acetone & ATF makes more sense to me.

I've had some good experience with ZEP 45, it's ingredients look like this:

(40-50%) - TRICHLOROETHYLENE; acetylene trichloride; 1-chloro-2,2-dichloroethylene 79-01-6
(15-25%) - PARAFFIN OIL; blend of heavy and light naphthenic petroleum distillate 64742-52-5
(5-15%) - MINERAL SEAL OIL; mineral oil; petrolatum 64741-44-2
(1-10%) - TETRACHLOROETHYLENE; perchloroethylene; perc; carbon bichloride 127-18-4
(1-10%) - Calcium alkylnaphthalenesulfonate Proprietary
(1- 10%) - DIETHYLENE GLYCOL MONOBUTYL ETHER; 2-(2-butoxyethoxy)-ethanol; butyl carbitol 112-34-5
( (

Liquid Wrench looks like this:

(60-100%) - Methyl soyate 67784-80-9
(7-13%) - Hydrocarbon Fluid 64742-47-8
(3-7%) - Tripropylene Glycol Monomethyl Ether 25498-49-1
(1-5%) - Corrosion Inhibitor Proprietary
(0.1-1%) - PTFE/boron nitride colloid Proprietary
 
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ATF and brake-fluid don't mix (ATF floats) so I'm not sure how effective this mix really is.


It certainly does mix and it is very effective. The brake fluid proves surfactants, corrosion inhibitors, ester friction reduction, the phos in the ATF diffuses into the rust to break it up, and the friction modifiers in the ATF reduce torque.

It is safer than the mix of ATF and fuel system cleaner I mentioned earlier.

If you are concerned about chemical toxicity, use gloves. People change oil all the time without realizing the plethora of toxins that are contained in used motor oil.

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If I were making a home made penetrating fluid, I would use the thinnest fluid I could find with some lubricating qualities.

Someone mentioned Berryman's B-12 and it does contain about every solvent available for fuel systems cleaning. But use gloves, it contains some nasty stuff.

One of the components you want in a penetrating fluid is something called a "surfactant." I'll let you Google that. The solvents and acetone help with that.

The other component needed is a lubricant to hold the surfactants and to provide fricton reducton. The thin base oil of ATF helps with that.

Another component you want is an Anti-Wear agent and ATF contains about 300 ppm of anti-wear agent TCP (or similar) to help twist bolts wthout galling. It also attacks the rust.

So for a quick, home made penetrating fluid, I would suggest 25% B-12 Chemtool® Carburetor, Fuel System and Injector Cleaner and 75% DexronVI, OR 25% B-12 Chemtool® Carburetor, Fuel System and Injector Cleaner and 75% Valvoline's Maxlife 6 cSt ATF.

Be careful with anything containing acetone or ANY ketone, since it may attack elastomers and paint.
 
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Originally Posted By: MolaKule
It certainly does mix and it is very effective.

Well mix some up and show me. I tried (from a fresh, sealed bottle) and it settled out in an hour or so. I'll try another batch tomorrow and see how it goes.
 
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I admixed a cheapo, off-the-shelf DOT 3 brake fluid with QuakerSate UATF (both purchased at a Farm and Home type store), 100 mL of each in a 250 mL cylinder, and let it sit in the cold garage for about 5 days.

To this day, there is absolutely no separation whatsover.
 
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