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Accidently left brake fluid cap off

Unreal1

Autocross Champion
Location
Pittsburgh
Excuses aside, I accidentally flushed two of my breaks without the brake fluid reservoir cap on. I was flushing the manual method, pumping my brakes. Just wondering if there's any chance that I sucked in a lot of air? The reservoir was pretty much filled to the top, so I'm thinking I should be ok? If not, I'm guessing I'll have to buy more fluid and flush the entire system again?
 

ashchuckton

Ready to race!
Location
Ohio
If your brakes are feeling good you will be OK. You will only suck air in if the fluid level gets too low. So how do the brakes feel?
 

Sootchucker

Go Kart Newbie
Location
Cheshire, UK
Car(s)
MK7.5 GTI (2018)
As well as spongy brakes, I'd also be worried that brake fluid may have spilled out into the engine bay which is a great paint stripper !
 

VictorHuge

New member
Location
Toronto
Where did you get the impression that the reservoir cap must be on when bleeding?

I'm sure you're fine so long as you didn't run low on fluid
 

George Ab

Drag Racing Champion
Location
Pacific NW
It's fine. When done manually pumping the brakes, with the cap off sometimes fluid can splash out of reservoir. It's a non-issue. Once you bleed with a bleeder pump you will never go back. Much easier, and most importantly you will not have a chance of scoring master cylinder with contaminates as the piston goes all the way to bottom which it normally never does.
 

Gibberoni

Ready to race!
Location
Simpsonville, SC
You actually don't want the cap on 100% when bleeding the brakes IIRC. You just want the cap on enough to cover the reservoir from getting contaminates in it.
 

Jose_Gti

Autocross Newbie
Location
Philadelphia
The same happened to me! XD the bottle I was using was not sealing properly, not enough pressure, so I kept on telling my wife to continue pressing the pedal... at the end I had to add more fluid and repeat the process until the liquid was coming out without bubbles...
Anyway cap on or off IMO it's better to leave the cap off and check the fluid. The cap being too tight I don't think it matters as long as the fluid is coming out and the reservoir is not too low so the air doesn't enter into the system.
I also change the oil AND forget to put the oil cap back on so when I started the car I got the check engine light on... it took me 10 minutes to realize that it was the oil cap he he he At the end it was as simple as clearing the code with OBD eleven (and putting the cap back on) embarrassing moments....
 
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