taylorslandy72
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Hi all, been out trying to bleed all the brakes on the s3 and couldn't stop getting air through, found out I was using some old fluid, is this what happens when it's gone off?
Brake fluid shelf life!!!!!!!
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no.
it's hygroscopic so absorbs water which can rust internals and lower the boiling point, so your brakes boil when heavy braking; which is why you are meant to change it every x years
it's hygroscopic so absorbs water which can rust internals and lower the boiling point, so your brakes boil when heavy braking; which is why you are meant to change it every x years
smnbyt
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I didn't think the new synthetic fluid was hyoroscopic?
Silicone fluid (dot5) is not hydroscopic but dot4 is. The dot 5 can get water droplets that will can cause corrosion and if you worry about the reduction of boiling point of normal fluid, then water will be much lower.
taylorslandy72
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I was using some unopened tins of duckhams brake fluid that was WAIT FOR IT almost 30 years old
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don't stick dot5 in. it doesn't mix with 3,4,5.1 and will cock things up.
you'd need to do a proper purge if you want to use it... and like there's not too much point really
you'd need to do a proper purge if you want to use it... and like there's not too much point really
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the tins might be alright you know.. plastic i dunno, i'd use unopened plastic if it was a few years old.
but it's cheap enough to not risk it
but it's cheap enough to not risk it
TooMany2cvs
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That's a "Thanks, no thanks" from me...
I've got a few cars that I really need to change the fluid in, and have just done the brakes on the 88, so decided to stock up a bit...
Shell DOT 5.1 High Performance Brake Fluid Car / Bike - 3 litre ltr | eBay
6 x 500ml Shell DOT5.1 for £14 delivered.
A bottle and a bit did the brakes and clutch on the Landy.
TooMany2cvs
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DOT5.1 is not DOT5.
5.1 is glycol based, like DOT3 & DOT4, but with a higher boiling point.
5 (.0?) is silicon based, and not miscible with glycol-based fluids.
And the water helps to corrode everything from the inside out
smnbyt
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Bargain......Just ordered myself some, to good an opportunity to miss, Nice one for putting the link up
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Oh, I see. That's not confusing at all.
TooMany2cvs
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Tell me about it! DOT stands for Dept of Transport, USA - which explains _everything_... <grin>
It does make a bit more sense than it first seems. DOT3 was the "main" standard, which was improved for DOT4, with higher boiling points, as technology improved. Then DOT5 was introduced, still higher, and it wasn't hygroscopic (moisture-absorbing!) GREAT! Except... it was found to be really difficult to bleed, and wasn't miscible. So a revised standard - 5.1 - was introduced. Same higher boiling point, without the drawbacks, but still hygroscopic. And that's where we are today.
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