Technical Changing brake fluid - how often?

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Technical Changing brake fluid - how often?

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I've just changed my brake fluid on my Seicento because it was 2 years old. After speeking to some 'professionals' they seem to think that it doesn't need doing after just 2 years. One comment was that my car wasn't fast enough to benefit. Another was that "it's just a way for us to make extra money". It seems that nobody does a brake fluid change unless there is a problem.

I am right in thinking that it should be changed every 2 years aren't I? It's also every 2 years for good reasons isn't it? Apart from brake fade etc., it can cause things to rust resulting in sudden brake failure can't it?
 
alternativly, bleed every month, a small amount, that way you get rid of the worst fluid (the heated stuff) and every year will have had a comlete change.

I haven't tried them yet but speed bleeders look interesting.

I've had a service at a main dealer where the change was called for.....a week later i bled myself, and i hadn't look like it had been done!

not worth skimping imho.

Kristian
 
alternativly, bleed every month, a small amount, that way you get rid of the worst fluid (the heated stuff) and every year will have had a comlete change.

I haven't tried them yet but speed bleeders look interesting.

I've had a service at a main dealer where the change was called for.....a week later i bled myself, and i hadn't look like it had been done!

not worth skimping imho.

Kristian

Isn't every month a bit excessive? I wouldn't been keen on using brake fluid that had been open for months (otherwise you need a new bottle every month).

The biggest inconvenience with changing the brake fluid are the problems that you can get. This time when I did it the bleed valve rounded, and nut on the brake pipe rounded too when I tried replacing the brake cylinder. The brake cylinder is in my bin now, with the pipe still attached. I've got a new brake pipe now, but it did take a while and cost a bit.

Any ideas how I can help keep the bleed valves moving? Is it worth greasing them?

I tried one of the pressure bleeders, but wasn't too impressed. It didn't seem to fit very well. I used a cheap kit from Screwfix this time. It's very simple, just a pipe going into a container with another pipe for air. I did it on my own and it seemed OK.

I did my first service, which was relatively small, oil, filters, and plugs IIRC. For the next service it needed coolant, and brake fluid changed, so I decided to pay somebody to do it. Unfortunately at the end of the service he told me that the coolant and brake fluid would be OK for another year. So it wasn't such good value, and I could've done it myself quite easily anyway. Since then I've done all my servicing and most of my repairs.
 
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You are ok using an opened bottle for a year.....the trick is to squeeze the bottle so the fluid is to the brim and then reseal. That way no air and moisture is in there.

No need to worry as the fluid in the reservoir will be as old after a year, and been in a much harsher environment. Leaving th ebottle open for a year and obviously its junk though

The way to keep things freed up is also to use them often, they don't get chance to seize then.

This is not the only way to do things, but is often done on track day and other sport cars after every use, to get rid of the most affected stuff, without the expense of changing fluid each time.

I wouldn't recommend greasing the nipples/valves, if they are a bit old and worse for wear, replace them for new, and they should last a while before they seize again.

http://www.brake-pipe.co.uk/ is a good place to get new cheap valves from.

Kristian
 
As aged brake fluid being hygroscopic has taken a considerable amount of water taken on, brake lines and brake piston will suffer. This is one reason why it should be changed every other year.

The only way getting round it is using silicone brake fluid. But is has got one down side. It brakes up seals unless tey are being swapped with seals made for the use.

Cheapest option long term is to change it as recommended: Every 2 years.
 
We had an 85 Polo C in the family for 17 years and 115,000 miles. It never had a brake fluid change. Just a top up when a rear wheel cylinder was changed at around 70,000.
The other cylinders were fine after 17yrs with no brake fluid change.

Why? Because the `old man` would never allow it to be changed during my servicing of the car:(

" It doesnt need it" he used to say. For 15 of the 17 years I waited for the wheel cylinders to rust or seize, or the brakes to fail, but no.

At the end of all that time he said "told you so"

Parents......(n)

( I change my own fluid every 4 or 5 years as a result of that experience)
 
We had an 85 Polo C in the family for 17 years and 115,000 miles. It never had a brake fluid change. Just a top up when a rear wheel cylinder was changed at around 70,000.
The other cylinders were fine after 17yrs with no brake fluid change.

Why? Because the `old man` would never allow it to be changed during my servicing of the car:(

" It doesnt need it" he used to say. For 15 of the 17 years I waited for the wheel cylinders to rust or seize, or the brakes to fail, but no.

At the end of all that time he said "told you so"

Parents......(n)

( I change my own fluid every 4 or 5 years as a result of that experience)

How ragged was the car though? A good blled of my brakes solved the fading problems.

How often you want to be changing it also depends on the use you're expecting to give it.
 
How much fluid did it take in total? So I can go and buy my bottle! and it's DOT3 or DOT4? Thank you

It's just under 0.5l on the 899cc ones, and I'd expect it to be the same on the 1.1's too. I always get two 0.5l bottles because I usually end up needing just over one bottle.

I think it's dot 4 isn't it? I don't think cars use dot 3 these days do they?
 
has anyone ever tried dot 5.1 on a cinq?
It is meant to be compatible with dot 3 and dot 4, and have high boiling point and other racing like properties similar to dot 5.

Also the other day I came accross synthetic dot 4. What is that? I thought only dot 5 was synthetic?
 
Also the other day I came across synthetic dot 4. What is that? I thought only dot 5 was synthetic?

DOT5 is Silicone based and completely incompatible with everything else.

There are synthetic DOT4 fluids that have higher boiling point that DOT5.1 (not mega expensive DOT4 either), so don't assume that DOT5.1 are better.
 
oh ok, cool didn't know that. I always thought 5.1 was the best around.
But the other day I bought some Dot 4 and it had written synthetic on it, and found it strange... Aspecially since it said it is still compatabile with normal dot 4.

Cheers for the info.
 
For road use I'm struggling to find anything with a higher boiling point (wet & dry) that Castrol Super DOT4.
Just a shame that it seams Halfords don't stock it anymore.
 
Here are some of our regular Maltese events (though I am there no more)
http://picasaweb.google.com/nadir.syedsammut/20070607HillClimbTaQali

TaQali `strip`..... The Old Man was there with the RAF when the Regia Aereonautica came over and dropped a 500lb bomb next to him. ( amongst hundreds of other bombs)

It didnt go off ( obviously) I think Fiat had a hand in it, but it sort of had build faults on delivery(y)

Apparantly the Fiat engined bombers used to come over at very high altitude to avoid rain and fears of water entering the double skin..........

( All true except the last para, allegedly:D
 
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