Brake fluid change

[dazzz]

I want to replace the 5.1 with Motul RBF600 dot4.

What's the best way to do this to ensure all the 5.1 is removed?

[JohnnyC]

Bleed it

[Ianboom]

Did mine a couple of weeks ago, luckily?? the old fluid was dark brown, so when the new fluid came through, it's was easy to see.

I got a large syringe and sucked out as much old fluid from the master cylinder resevoir, and replaced it with new, then I bled one caliper at a time (got my 6 year old to pump the brake for me!) and kept checking the fluid resevoir topping it up when necessary.

I put a block of wood under the brake pedal to stop it travelling to far as apparently this can damage the seals. I also ran the engine as the pressure from the system helped push the fluid through faster.

Took me about 2 hours to do on the drive and cost me a packet of Haribos!!

[jasongtr]

just bought a vacuum thingy to whack on my airline to do mine

[Harold]

Buy a Gunson eezibleed, it turns a brake fluid change into a very simple and quick one man job.

[jasongtr]

does that still need the pedal pumping, id rather not risk damaging the seals

[Harold]

does that still need the pedal pumping, id rather not risk damaging the seals

Nope, you use a spare tyre at 20psi to pressurise the system and force the new fluid through.

[jasongtr]

oh ok, the one bought needs 90-120 psi to create the vacuum, would that one work ok at just 20psi?

[Torero]

Buy a Gunson eezibleed, it turns a brake fluid change into a very simple and quick one man job.

I got a similar one as well Harold, simple job [after a bit of faffing around trying to fit the reservoir seal] but no pedal pumping needed and it was 20psi.

@JasonGTR - The one you have sounds as if it is for aircraft Jay

@IanBoom - Agree mate, it was far more effective with the engine running, making the servo vacuum run seemed to make the finished job far better.

[jasongtr]

hah i thought it sounded alot, but maybe as its creating the cauum to suck the fluid through at the bleed nipple, where as those tyre ones sound like they push it from the res - i dunno but they all seem ed to be 90-120psi needed from the compressor

[Ianboom]

I nearly bought a bleed kit that would work with my compressor, but thought I'd never use it again.

Spoke to the neighbour a few days after doing the brakes and found he had one

If you live near Solihull I can lend you a 6 year old for the price of a bag of Haribo

[RST]

Bleed it [Smile]

...drain it I would have thought. Bleeding will just get rid of air. When I change fluid I use a small tube with a one way valve in it. I got mine from Halfrads for a fiver. You can use the other pressure systems or put a tube from your caliper nipple into a jar with brake fluid into it and do it with 2 people but the £5 eazy-bleed tube has been one of the most effective tools I've used in years.

I can't remember the flusing sequence but you do the caliper in turn opening up the nipple and pressing on the brake pedal, every few presses (4 or 5) do to the rerservioir and top up the level then back to the brake pedal / calliper etc. It's as easy as that.

Just costs you a fiver for the tube, an empty bottle to collect the fluid (which you'll have to empty into a bigger one and take to the oil bund at the local tip, I use an old juice bottle then tip it into a bigger one for each corner) and the cost of the fluid.

The tube's made by gunson I think. Ranks as one of my best spent fiver tools ever, can't believ how easy it is to bleed/flush fluids with it.

[JohnnyC]

Bleed it [Smile]

...drain it I would have thought. Bleeding will just get rid of air. When I change fluid I use a small tube with a one way valve in it. I got mine from Halfrads for a fiver.

No, just bleed it.
As someone said above, you can often tell when the new fluid starts coming through.
And I use one of those cheap one-man kits from Halfords with the one way valve in the tube too

[Shmed]

How much fluid is there in the system? I seem to remember someone saying a litre is plenty to flush the whole system. The sequence is determined by distance from the master cylinder. Do the furthest away first, n/s rear, then o/s rear, the n/s front then o/s front. If replacing fluid, it makes sense that you should take longer doing the first one and progressively less for the others.

[adam_ep82]

Did my whole system couple of weeks ago a litre is plenty

[JohnnyC]

How much fluid is there in the system? I seem to remember someone saying a litre is plenty to flush the whole system. The sequence is determined by distance from the master cylinder. Do the furthest away first, n/s rear, then o/s rear, the n/s front then o/s front. If replacing fluid, it makes sense that you should take longer doing the first one and progressively less for the others.

Correct, bleed more from the calipers that are furthest away.

The system can be bled with 500ml, but you can use a litre to be sure.
And there wouldn't be any problem with having a bit of dot 5.1 left in with dot 4.