Changing brake pads

antz91, Feb 28, 2:29am
I was recently taught a way to change them but wanting to know if it' ok.

Im fine with the unbolting everything but the 'pushing in the cylinder' bit im a bit iffy on. Wouldn't dirty break fluid get back into the resivour and mix with the clean one!

Cheers.

whqqsh, Feb 28, 2:36am
no point because youll have to get some of the brake fluid out of the reservoir first or else when you push the piston back it will overflow, I use a big syringe I got from the vet

antz91, Feb 28, 2:49am
Whoops forgot to mention that. I take out some so it doesn't overflow. But is this method ok!

morrisman1, Feb 28, 2:54am
because with worn pads the calipers have a lot of fluid in them (piston at longer travel) and when you push the piston back in to fit the new pads on the fluid gets pushed back to the reservoir.

You could open the bleed nipple as you push the piston back in, dont get brake fluid anywhere it shouldn't be! I usually get some clear plastic tube and push it on the bleed nipple so it drains into a jar

smac, Feb 28, 3:10am
But where do you think the extra fluid in the piston barrel came from.think carefully.

illusion_, Feb 28, 3:19am
why would the fluid be "dirty"!

think about it

cp.71, Feb 28, 4:11am
If you have ABS brakes DO NOT force the fluid back into the brake system. It has the potential to stuff the abs pump unit. Brakes will still work, but will / should fail WOF

intrade, Feb 28, 4:15am
you are supposed to change brake fluid every 24 month. so it would not matter when you push some back up. Here is how else to do it correct the 24 month still apply. you open the bleeder nipple and then connect a hose on it and now push the piston back the exess oil comes out of your open bleeder. shut bleeder fit brake reasemble and then bleed any air out again of the brake system by pushing pedal to floor with nipple open and then shut nipple and release brake pedal repeat few times and top up if requred usually 2 person job to bleed brake.

intrade, Feb 28, 4:18am
the extra fluid comes from topping up when brake get low front and rear wear out so you top it up when the brake light comes on when you now retract the piston you likely will have the resaorvoir overflow

intrade, Feb 28, 4:20am
brake fluid collect moisture its why you change it after 24 month i got a divise reading the amount of water in fluid. and wof places in europe pop that in your brake fluid every wof to check you dont brake with water.
exactly that one i got
http://direct.247spares.co.uk/accessories/car-parts/car-care/secor--t-brake-fluid-tester:364329

phillip.weston, Feb 28, 4:21am
yeah I would definitely crack the bleed nipple and attach a one-man brake bleeding tool (basically a clear tube 50cm long with a one-way valve at the end, available from repco/supercheap for approx $25-30) and push the piston back in with the excess fluid being expelled. It is generally a good idea to flush out the brakes with say 250-500ml of fluid anyhow as no doubt the brake fluid hasn't been replaced periodically like it should be, and has gone from the light yellow/golden original colour to a dark brown colour as it absorbs moisture, rust and other debris from inside the brake system.

morrisman1, Feb 28, 4:31am
I was kind to the old beast and put new fluid in it the other week, the old stuff that came out was obviously old, brown in colour and colour didnt remain consistent as it was flushed out (some patches darker) and in one wheel it came out looking like an emulsion which sat on the top of my brake fluid jar.

Id be surprised if more than 10% of the cars on the road had their brakes properly serviced

morrisman1, Feb 28, 4:42am
I wasnt claiming that mine was properly serviced, it will be from now on for as long as I own it.

fordgod, Feb 28, 5:06am
Agree!

Seen it to many times, leaking cylinder after brake bleeding, above quote is 90% of the time, the cause of the leaking. As biker quoted, I always pump the pedal within normal stroke range and never have any probs with leaking master cylinders even with all my old cars.

unbeatabull, Feb 28, 5:19am
What if its had a brake bleed since the new pads were fitted! Brake Fluid is suppose to be changed & bled every 2 years, so if the pads were due after 3 years its going to have a bit of extra fluid in it :)

xs1100, Feb 28, 6:03am
so what considering the price of brake fluid its just as easy to bleed complete system when changing pads that way job done properly just remeber to always start from bleed nipple furtherest form b/master cylinder normally left hand rear

sr2, Feb 28, 6:03am
Any corrosion in the master cylinder is totally unacceptable and a potential safety hazard. Far better to have a master cylinder failure when bleeding than on the open road.

unbeatabull, Feb 28, 6:11am
^ This.

Most people are too tight to do a brake fluid change at the same time as pads, as silly as it sounds, when you consider a bottle of Brake fluid is ~$13 (esp when its not due for another 12-18 months), but we do get a lot of customers who do not want the fluid done at the same time, just pads.

owen110, Feb 28, 6:16am
Best way to stop the brake fluid going back into the mastercylinder is to clamp off the brake hose with [if you haven't got a proper hose clamp] lightly with a pair of vice grips.Put a drain hose on the bleeder and open it.Push in the piston with large pliers or what you have,close the bleeder off,fit the pads and put it all back together.

antz91, Feb 28, 6:44am
Man that was a good read. You learn something new everyday. Cheers guys.

xs1100, Feb 28, 8:17am
better to use the clamps avaliable from supercheap/repco they are yellow and made of plastic.remeberin-
g that brake lines are made of rubber and perish over time so vice grips can tear the rubber/damage them easily

sr2, Feb 28, 8:19am
Nonsense.