View Full Version : burning brake fluid: good or bad idea

07-04-2008, 06:01 PM
I have about a half gallon of brake fluid leftover from bleeding brakes and clutches. I was thinking of putting some small amounts of it in my used motor oil and burn it in order to get rid of it.

Is this a good or bad idea?

07-04-2008, 06:17 PM
My first thought was sure it will burn. I would even say you could burn it straight. I did a search and came up with this though that doesnt sound so good.

Burning brake fluid or chlorinated solvents like methyl-ethyl ketone results in the production of hydrochloric acid, which in turn can corrode parts of the furnace and cause acid rain.


Pretty certain that one gallon isnt going to change the current problems our globe has but your gallon mine and fifty thousand others might. This is part of the conundrum that oil burners face though. On one side it is making use of something that is an environmental hazard while disposing of it instead of shipping it offshore to be incinerated but on the flip side it is without a doubt releasing small amounts of pollutants into our atmosphere.


07-04-2008, 07:35 PM
Well, brake fluid sounds like a bad idea then.

07-04-2008, 10:10 PM
I lit some on fire on accident once, my tr7's brake fluid reservoir had a hole in the top and spilled some on the exhaust manifold whilst i was driving at an enthusiastic pace. It burns green and smells #@*% horrible.
Based on that, i'd say no :P

07-04-2008, 10:19 PM
... On one side it is making use of something that is an environmental hazard while disposing of it instead of shipping it offshore to be incinerated but on the flip side it is without a doubt releasing small amounts of pollutants into our atmosphere.
Well we'r wanting to build incinerating furnaces aren't we :?: :P

07-04-2008, 10:54 PM
Thats my point have heat, why not incinerate and get something instead of incinerating and getting nothing but the pollution.


07-05-2008, 05:17 AM
I prefer to mix Brake Fluid with Potassium Permangenate and get a big purple fireball that is hot enough to melt metal. You get 45 seconds from when the chemicals are combined to when it ignites...

Though I don't know about used, I did my experiments with new brake fluid. It does stink something awful when being ignited, but once it is burning hot and clean it isn't too bad.

07-05-2008, 06:35 AM
You can mix it with pool chlorine too.
Ignition time depends greatly on the temp of the ingredients when you mix them.
Roughly speaking, you have a minute at 60*f, 30 seconds at 70, 10 at 80, and none at all at 90 or above.
Not something for a hot summers day!

The fumes are, of course, nasty at best.

07-05-2008, 07:14 PM
I always dump any that I have in my w/o drum, but adding a pint or so to a 55 gal drum of w/o isn't likely to make a noticable difference.


07-06-2008, 01:25 AM
I'd just do like welder19 said and dump it all together if you got the oil to delude the brake fluid.

If you get any WO from an auto shop your not going to know what's in it, so may as well get used to it.

07-06-2008, 01:40 AM
I know it'll burn, I just mainly wanted to figure out if there were any major health effects I was unaware of. That being said, I'll probably be getting in the practice of wearing a respirator anyway when burning oil, melting metal that may have lead, zinc, etc, in it. I also hear copper fumes aren't great to breathe.

I suppose the other concern is what effect the burning of brake fluid diluted in oil has on the refractory.

Good point on shops, I'd be willing to bed a large percentage of them put brake fluid in the WMO.

07-06-2008, 04:27 AM
We might, sometimes, perhaps, in theory.

Basically anything that can't go in the trash can goes into the WMO barrels in most shops.
We have a coolant barrel as well as a recycling machine (nasty nasty goes in the barrel, kinda-nasty goes in the machine to be cleaned into $10/gallon product, gotta love that, it paid for itself in like two loads), but coolant still ends up in the barrels due to cars that get water in the oil from a head gasket issue or somesuch.

So there is oil, obviously, some synthetic oil (mostly pretend synthetic like mobil1 and castrol syntec which is still petroleum base stock and burns fine, but some true synthetic which doesn't burn for shit), some gasoline, some gear oil, some ATF fluid, some coolant, some miscellaneous oil filter sludge, a fair amount of carbon (the black in oil is mostly carbon), some gasket scrapings, some aluminum, some iron, some lead, some tin, some bismuth, some solvent, some misc. grease brought in with the solvent, i think thats most of it. You get the idea :D
It averages out pretty well, but one barrel or load to another you can expect some energy density changes. Avoid places that work on a lot of sports cars, you synthetic oil is fairly useless fuel wise, it burns slowly and only when exposed to very high heat.
Side note: Don't use synthetic oil in mazda rotary engines, they intentionally inject some oil into the combustion chambers to lube the rotor tips, synthetic doesn't burn well enough and gums everything up, which in turn leads to stick rotor tips and low compression and oil burning.

07-06-2008, 04:35 AM
Speaking of synthetic, the first oil burner test I did, had 5 quarts of "royal purple" from a buddies WRX, and about 3 quarts of 20w-40 yamalube from my bike. (Which is the same test you see in my oil burner site)

How does the coolant recycle deal with the acid in used coolant?

07-06-2008, 06:05 AM
You add more brand new coolant to it, neutralizes the acid and brings it back towards basic.
In theory coolant, even used, shouldn't have any acids in it, the only source for acids is exhaust gasses, which ought not be in coolant. Of course, they do show up from time to time, enough to keep me constantly changing head gaskets at least.

You can buy concentrated basic-glop and toss that in, but since we're recycling it to a 50/50 premix (rather then shooting for raw coolant/anti-freeze) it's easier just to toss a gallon or two of new (ok, recycled by someone else to full raw strength, but close enough) coolant in.

I can't remember whether royal purple is a petroleum base stock or not, if it's a genuine synthetic i might be wrong about furnaces and synthetic, it's possible that they're so ($%& hot it doesn't matter.

07-06-2008, 06:17 AM
In theory coolant, even used, shouldn't have any acids in it, the only source for acids is exhaust gasses, which ought not be in coolant.

In theory yes. However my MX-6's (that was in an accident) has 2 different metals in the coolant system (I forget what besides aluminum), which I've heard has the effect of turning the coolant acidic in about 9-10 months, which is why on these cars you have to change the coolant yearly.

Is the PH of the recycled coolant measured before putting it in customer's car?

I just checked Royal Purple's website:

Royal Purple Motor Oils are composed of a proprietary formulation of synthetic base oils and synthetic additives containing iso-paraffinic diluents.

07-06-2008, 07:14 AM
Yeah, the SAE(Society of Automotive Engineers) has declared that highly refined petroleum can be called Synthetic, regardless of the fact that it has none of the qualities of ester based genuinely synthetic oils, those being extreme strength and temp resistance.

I'm going to have to look into the different metals bit, i know they can cause issues if there isn't enough coolant in the system, the water acts as an electrolyte and the aluminum starts getting eaten by electrolysis, this causes many a dead head on toyota 22R motors.

07-06-2008, 07:10 PM
I talked to my buddy who uses the Royal Purple, and he's pretty sure it's a "true synthetic"... take that for what's it's worth.

07-16-2008, 04:33 PM
I've right now got four tuna cans filled with used brake fluid from bleeding my car out back simmering away.

It seems to me like this won't work in a regular oil burner, at least not without a good choke.

Right now all four cans are burning from the pool surface with no blower and no smoke, it's actually rather similar to the flames produced by sterno gel.

Meaning either a good choke, or mixing it with something air-hungry like WVO would run fine.

Brake fluid isn't really oil though, it is mostly Polypropylene glycol. As such, when ignited it burns fairly hot and clean, though I am not certain what kinds of impurities it is likely to get.

07-16-2008, 05:00 PM
Given the warnings attached to it and the fact that it makes a fantastic paint remover, my guess is that there is something nasty in there, otherwise astroglide would remove paint!

07-16-2008, 05:21 PM
I meant to update this thread anyway, thanks for reminding me.

I put a coffee can full of brake fluid in my oil tank and filled the rest with WMO (made from a 20# propane tank so you can do the math on the ratio there)

It burned/worked fine, did not produce any noticeable odors that were immediately toxic :) (That being said a respirator probably isn't a bad idea)

07-16-2008, 05:34 PM
Prolly ought to wear a respirator for burning oil anyway :P

07-16-2008, 05:38 PM
Prolly ought to wear a respirator for burning oil anyway :P


Plus what if something your melting has zinc or some other dangerous metal you may be unaware of?

07-16-2008, 05:42 PM
I did that, accidentally tossed some zinc flakes into my aluminum melt. Very pretty crystal blue flames. Oops.
At least zinc fume fever doesn't do lasting damage :P
I drink a ton of milk though, i'm probably immune. Not that i sat downwind to test that mind you, once it occurred to me that my BBQ charcoal fueled furnace shouldn't be putting out sharp blue flames i turned it off and pulled the crucible to find that it had a hole in the bottom and i was rapidly losing my aluminum.
That was a bit of a mess. The lesson learned: Don't overheat aluminum with salt flux in a stainless steel crucible.

07-16-2008, 05:48 PM
I noticed on my tuna cans that burning brake fluid doesn't seem to smell any different from burning hair.

Oh wait.

Dangit there goes my arms again. Got a bit too close to it while adding another bleeder cup from my car.

07-17-2008, 05:01 AM

07-17-2008, 04:28 PM
Rofl, seriously, irl.

09-05-2008, 10:06 AM
Dunno bout you guys but i mixed brake FLUID with my WMO coz all kids of crap was comin out of that tractor...... Anyway my budget burner seemed to go better i reacon this is coz its mostly water but not sure

09-05-2008, 07:16 PM
Brake fluid is largely esoteric alcohols(glycols and such), it burns more easily then wmo does in my "tests". Those being accidentally spilling both on HOT exhaust manifolds, oil smokes, brake fluid burns with a very odd green flame.

It makes sense to me that it'd help a burner go better, though i bet it (slightly) reduces the total btus, which with waste fuel isn't really an issue.

09-05-2008, 07:59 PM
Brake fluid is bad to soak up water too, or is that good to soak up water. :?:

No one ever says anything about changeing your brake fluid, but you really should ever so often.