Washer fluid in the brake fluid - Oops!

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Hi, first of all, let me say this is not me, I'm not this stupid, as I know some of you like to come to that conclusion ;).

Right, a friend and work colleague of mine did something a little silly the other night. It was dark, and he was trying to fill up his washer water bottle under his bonnet. He'd never been under the bonnet of this car, and he found a cap and added some washer fluid to the container, only to be shocked to find the container fill up after only a few drops.

He then realised, all of a sudden, that it's actually not the water cap that he's been pouring it into, but the brake oil reservoir. He then proceeds to try and clean it out using kitchen roll to soak up the blue water of the fluid that had stayed at the top, until he started getting oil on the roll.

Now I've told him that this is can be very dangerous sticking the wrong stuff in his brake fluid, especially water, but he's so worried about how much it would cost to get his brakes bled, that he's still driving around.

Is it really that dangerous? Or could have get away with a tiny bit of this in his system? If it was me, I'd have gotten the system cleared out immediately.

The car is a 04 Nissan Micra by the way.

Cheers

Dave
 
I've just got to get him to understand how stupidly dangerous it could be, hopefully some more posts like that I can show him will sway him, as long as the car lasts til tomorrow, as he's driving to Leicester and back to Birmingham today. How much would a flush of the brake system cost at a garage?
 
What's the most important thing when driving?

STOPPING!

NEVER under any circumstance take silly risks over being able to promptly and safely stop.

Also, the washer fluid is quite corrosive stuff and will probably rot the brake lines if left in them.
 
When I see him tonight, I'll talk it into him as hard as possible, and if he turns round and says money is the problem, I'll give him the money, which he can pay back next year for all I care, as long as he gets it done ASAP.
 
As I understand it, it will get worse over time. If he uses the brakes a lot so they heat up, it might happen all at once and give him a shock. Handbrake and gears would be the best bet if that should happen

Maybe the brake fluid is more dense then water and he did get most of it out but tell him brake fluid has to be changed regularly anyway or it can cause much more expensive damage.
The service schedule would show this.
Its like anti freeze, it wears out anyway so he might as well do it now.


Pricing tends to go by car size and a micra wont cost much.


There was a case recently where a man used cooking oil for brake fluid, it didnt end well
 
Break fluid is hydroscopic which means it absorbs moisture- which is why it made Tesla's skin on his hands peel.
If the break fluid absorbs too much moisture (through just being old, or in this case becoming contaminated with screenwash :rolleyes: :D ) then it will not retain its properties which make it ideal as 'break fluid' ie when it is put under compression (breaking force) is will go all spongey thus reducing breaking force... which is baaad mmmkay? :eek: :D
Or something like that.
Get your m8 to get the entire breaking system flushed out and refilled with new clean fluid, better out of pocket a little bit than dead.
 
I will get worse over a matter of seconds once it reaches temp.

He'll come off the brakes with the lower line pressure with the heat from the brakes the fluid will boil creating air bubbles and voids. Next time he pressed the brakes he will have to compress the bubbles before he gets any hydraulic pressure in system to work the brakes.... whether he can do this in the length of a pedal stroke is something I'd hate to found out.

Also the fluid may well be denser than the brake fluid meaning it will sink the the caliper where the heat is. Not good.

Replace brake fluid fluid and reflush again with fluid, take no chances with this one.
 
Just an observation, but how does the brake fluid in the rest of the system get contaminated when only the resevoir was originally contaminated.

The fluid in the rest of the system should be fine and he will not have any problems with his brakes at all.

The brake system is not a circulation system there is no return feed from the calipers to the resevoir. The fluid just sits in the master cylinder, pipes, calipers/slave cylinders etc, getting moved back and forth as you press and then release the pedal.

Just empty out the resevoir and refill that with the same sort of brake fluid as he had before, as you cannot mix brake fluid types.

As I said just an observation, I am sure someone will tell me why that could not be done. :)
 
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