Mineral spirits in brake fluid?!

[Jaha24k]

So I was at the mechanics shop that I go to....I saw him check a van and he noticed the brake fluid was low. He grabbed a very old looking metal tin marked on the outside as "mineral spirits" with a pump attached to it and topped up with the clear fluid. I was pretty flustered. I had my rear brakes on my 4runner done by him a few years ago and now I'm wondering what the heck he could have topped my car up when he did my brakes. I mean there is the possibility that there was some type of brake fluid in that container that he fills up from a bull container. It's been a few years and I haven't really noticed much outside the fact that my brakes squeal in cold weather (likely cuz he used cheap pads). Should I look into having my brake fluid flushed or am I worrying too much?

As a note he's very popular and has many repeat customers mainly based on the fact that his prices are very low and he seems to only suggest services that are required.

Thanks

 

[demarpaint]

Maybe he pours brake fluid into that can because his pump fits the can. I have a feeling that's the case, but that doesn't mean the brake fluid is fresh.

 

[Langanobob]

Just ask him about the can. It’s probably a clean can that he repurposed to hold brake fluid because he uses a lot of it.

 

[charbaby]

Originally Posted By: demarpaint
Maybe he pours brake fluid into that can because his pump fits the can. I have a feeling that's the case, but that doesn't mean the brake fluid is fresh.
Originally Posted By: Langanobob
Just ask him about the can. It’s probably a clean can that he repurposed to hold brake fluid because he uses a lot of it.


Both of these^^^

 

[Ethan1]

Since you didn't ask at the time, it would be kinda weird if you called and asked now. Your only logical course of action is to order a test kit from Blackstone, hire a cat burglar to break in to his shop, and have the contents of that can analyzed. Then you can write an appropriate Yelp review.

 

[Ducked]

Originally Posted By: Ethan1
Since you didn't ask at the time, it would be kinda weird if you called and asked now. Your only logical course of action is to order a test kit from Blackstone, hire a cat burglar to break in to his shop, and have the contents of that can analyzed. Then you can write an appropriate Yelp review.

One possibility. A cheaper one would be to analyse the existing brake fluid, or request a fluid change (probably needed anyway) and analyse some of that.

Dunno offhand a definitive test for traces of mineral spirits in brake fluid and I'm not sure how (or if) Blackstone will do it, since it may require Gas Chromatography/HPLC.

If it was straight mineral spirits the brakes would probably have failed by now, it wouldn't mix with water and it wouldn't strip paint.

 

[Kestas]

One quick check is to sample some fluid and pour it in a bucket of water. Brake fluid will mix, mineral spirits will not.

 

[Ducked]

Originally Posted By: Kestas
One quick check is to sample some fluid and pour it in a bucket of water. Brake fluid will mix, mineral spirits will not.


I just said that.

But the concern may be contamination rather than straight substitution. Seems pretty unlikely though. If its a re-purposed container the first recipient might get contamination if it wasn't fully cleaned, but by now its been flushed with a lot of refills.

 

[Kestas]

Unfortunately, I have an embarrassing first hand experience with mineral oil in brake fluid. This was from using an old brake fluid container as a satellite container for mineral spirits.

Driving 20 miles after brake service, my brakes started locking up and overheating. The mineral spirits swelled all the components in my brake system. I had to replace the master cylinder and rebuild all calipers and wheel cylinders. Fortunately this was on my 1974 Torino, which was easy to work on and not too expensive for parts. I fixed it for under $50.

I learned the hard way to make sure all containers are properly labeled.

 

[JHZR2]

Some of the best brake fluids come in steel cans.

Many brake fluids do not. Plastic containers dont likely diffuse much moisture in, but Id suspect it could be some.

Id go with the basis of using a steep can to keep moisture out, and the ability to use a certain pump (though why a pump would be needed is somewhat beyond me).

A quick ploy would be to turkey baste some fluid out, stop by and ask for a top up...

 

[The_Nuke]

Originally Posted By: Ethan1
Since you didn't ask at the time, it would be kinda weird if you called and asked now. Your only logical course of action is to order a test kit from Blackstone, hire a cat burglar to break in to his shop, and have the contents of that can analyzed. Then you can write an appropriate Yelp review.

Personally, I think it makes more sense to hire some shifty-type from the wrong side of town to go steal the other customer's car and bring it to your place so you can take a sample of the fluid in the master cylinder to send off for the analysis. Once you have taken your sample, your temp-hire will need to return the vehicle to the original customer's home and leave no indication of what went down of course, so I would advise some caution when interviewing candidates for the GTA. You don't want to hire the first lug-head that wanders up asking for spare change, as he likely won't complete the second half of the job in question (which is the more important half of this kind of task in my opinion).

 

[Yah-Tah-Hey]

No problems in the years since he worked on your brake system so you are probably good to go. Time to find something else to worry about.

 

[RyanY]

As the others have said, it's probably fine. However, if you're OCD as many of us are, you have several options to make sure your fluid is okay. 1) buy the brake fluid test strips (about $11 for a 2 pack on amazon or 2) just change the fluid (about $10 diy).

A drawback of option 1 is that the strips test for water but probably not mineral spirits(?) I would choose option 2, given that you only need about a qt of brake fluid (depending on your vehicle req), about 5' of 3/16 ID vinyl hose, and an empty 2L soda bottle. Besides, it has been a few years and it is probably time to change anyway.

 

[maxdustington]

Originally Posted By: Kestas
Unfortunately, I have an embarrassing first hand experience with mineral oil in brake fluid. This was from using an old brake fluid container as a satellite container for mineral spirits.

Driving 20 miles after brake service, my brakes started locking up and overheating. The mineral spirits swelled all the components in my brake system. I had to replace the master cylinder and rebuild all calipers and wheel cylinders. Fortunately this was on my 1974 Torino, which was easy to work on and not too expensive for parts. I fixed it for under $50.

I learned the hard way to make sure all containers are properly labeled.


Awesome story, I imagine the ABS pump on a modern car would be twenty times that cost alone!

 

[Ducked]

Originally Posted By: Yah-Tah-Hey
No problems in the years since he worked on your brake system so you are probably good to go.


He doesn;t want to be good to go. He wants to be good to stop.

 

[Ducked]

Originally Posted By: RyanY
As the others have said, it's probably fine. However, if you're OCD as many of us are, you have several options to make sure your fluid is okay. 1) buy the brake fluid test strips (about $11 for a 2 pack on amazon or 2) just change the fluid (about $10 diy).

A drawback of option 1 is that the strips test for water but probably not mineral spirits(?) I would choose option 2, given that you only need about a qt of brake fluid (depending on your vehicle req), about 5' of 3/16 ID vinyl hose, and an empty 2L soda bottle. Besides, it has been a few years and it is probably time to change anyway.


First option is irrelevent, as you acknowledge, so why suggest it?

Second option fairly irrelevent too, since it doesn't tell you anything about the status of this mechanics brake fluid, the focus of the OP's (probably unwarranted) concern.

Changing brake fluid is a good thing, but any damage to the OP's system due to hypothetical mineral oil contamination was a done deal long ago.

 

[Silk]

We get brake fluid in a 20 litre bladder, no air gets in the container. We fill up our own bottles...I use an old 500ml brake fluid bottle, but one of the other guys uses an old drink bottle...So, he most likely buys in bulk, and uses the container he prefers.

 

[Ducked]

Originally Posted By: JHZR2
Some of the best brake fluids come in steel cans.

Many brake fluids do not. Plastic containers dont likely diffuse much moisture in, but Id suspect it could be some.

Id go with the basis of using a steep can to keep moisture out, and the ability to use a certain pump (though why a pump would be needed is somewhat beyond me).

A quick ploy would be to turkey baste some fluid out, stop by and ask for a top up...


The China Petroleum Corporation DOT3 I use comes in a plastic bottle, the DOT4 in a steel one, I think reflecting its greater vulnerability to water.

I'd quite like to store my unused fluid in a metal bottle, but I dont want to buy DOT4, and I think its too difficult to clean a mineral spirits bottle thoroughly enough.

I keep the used fluid in a whisky bottle. I may eventually get around to decanting the unused stuff (currently kept in its original bottle in many layers of plastic bags with a dessicant sachet) into another whisky bottle.

What could possibly go wrong?