Pushing back pistons on BMW Brembo calipers?
Discussion
I don’t have a fancy tool. It looks like Lisle do a pad spreader that’s work ok, but £60.
https://www.amazon.co.uk/Lisle-29100-Quick-Quad-Sp...
There are some ratchet types for cheap that sit between some pads to push on pistons, but it’d need a caliper off the disc, so no use just swapping pads.
Does anyone here just use levers on the old pads between pad and disc, like nylon trim levers, screwdrivers etc?
Was thinking you could push back one side, put a wedge in, then push back opposite side?
Even just an appropriately shaped piece of wood once you open up a small gap?
Calipers are 6.5yrs old so assume shouldn’t be corroded and should push back nicely. If not a spray of wd40 and left for 30 mins?
Only worked on single piston sliders previously and Judy used a screwdriver/lever for this job… or appropriate tool for winding rears (thankfully not a thing on BMWs with drum handbrake)
https://www.amazon.co.uk/Lisle-29100-Quick-Quad-Sp...
There are some ratchet types for cheap that sit between some pads to push on pistons, but it’d need a caliper off the disc, so no use just swapping pads.
Does anyone here just use levers on the old pads between pad and disc, like nylon trim levers, screwdrivers etc?
Was thinking you could push back one side, put a wedge in, then push back opposite side?
Even just an appropriately shaped piece of wood once you open up a small gap?
Calipers are 6.5yrs old so assume shouldn’t be corroded and should push back nicely. If not a spray of wd40 and left for 30 mins?
Only worked on single piston sliders previously and Judy used a screwdriver/lever for this job… or appropriate tool for winding rears (thankfully not a thing on BMWs with drum handbrake)
I stress I haven't worked on those calipers but I have never come across a caliper that isn't wind back that can't be done by just rocking the caliper by hand when it is unbolted from the mountings, and then levered further by a large flat screwdriver etc when there is enough gap.
I 100% doubt you would get that tool in there without first fully removing the caliper anyway.
I 100% doubt you would get that tool in there without first fully removing the caliper anyway.
I think you’d have to pry the pads a bit to get some play, then remove them, then use the tool.
But in theory you could just put a pair of screwdrivers in and use the pads as a load spreader onto the pistons.
Obv you’re replacing pads so no big issue if they get a bit damaged.
In my case I’m doing front discs/pads, and rear pads.
Caliper bolts are single use, so avoiding removing rear calipers needlessly to save £15 on bolts.
There are a few good videos on YouTube but they use the fancy tool above.
A few others simply omit the pushing back of pistons.
The main issue obviously is pushing a piston in, and having others pop out!
I think for that reason I’ll just chock/lever between disc and pads so there is never any scope for pistons to move beyond their normal stroke.
Only once the pistons are fully back will the pads come out and/or caliper come off.
But in theory you could just put a pair of screwdrivers in and use the pads as a load spreader onto the pistons.
Obv you’re replacing pads so no big issue if they get a bit damaged.
In my case I’m doing front discs/pads, and rear pads.
Caliper bolts are single use, so avoiding removing rear calipers needlessly to save £15 on bolts.
There are a few good videos on YouTube but they use the fancy tool above.
A few others simply omit the pushing back of pistons.
The main issue obviously is pushing a piston in, and having others pop out!
I think for that reason I’ll just chock/lever between disc and pads so there is never any scope for pistons to move beyond their normal stroke.
Only once the pistons are fully back will the pads come out and/or caliper come off.
Loosen the bleed screw after attaching a length of piping or a bleed tool and the pistons should push in with finger pressure. If not they probably ought to be removed for cleaning and seeing if there is corrosion under the caliper seal too.
I always lift the dust cover and check for corrosion before pushing the pistons back all the way, a squirt of silicone spray helps too.
You can also have hours of “fun” removing the steel pad retaining pins from certain Brembo calipers, Alfa Romeo owners will know what I mean!
I always lift the dust cover and check for corrosion before pushing the pistons back all the way, a squirt of silicone spray helps too.
You can also have hours of “fun” removing the steel pad retaining pins from certain Brembo calipers, Alfa Romeo owners will know what I mean!
Not sure I want to risk air into the brakes and bleeding as I have no bleeding kit or spare fluid… just had fluid done at BMW so likely will need to remove some.
Gonna just do it the boring/slow way. At least until I’m familiar with these kinds of caliper.
£720 for front discs/pads and sensor, and rear pads and sensor. Eeek.
Thankfully they get 6yrs/45k on a set which is pretty good.
£300 saved on labour. Instantly gone on vet bills got the aged cat
Gonna just do it the boring/slow way. At least until I’m familiar with these kinds of caliper.
£720 for front discs/pads and sensor, and rear pads and sensor. Eeek.
Thankfully they get 6yrs/45k on a set which is pretty good.
£300 saved on labour. Instantly gone on vet bills got the aged cat
It’s not just the bottle, it’s someone (wife) to pump the brake while you tighten the nipple.
Which then means young kids running around while she’s sat in the car up on jack stands, tools all over etc.
Then the nipple risk. Moron over-tightened it, leaves you with a car on stands for a week as it shears?
Then the spare brake fluid.
Then disposal.
Or the extra kit again to pressurise the brake reservoir to avoid the need of the wife/kids combo.
It’s seemingly a lot simpler to not go down that path if it’s not necessary isn’t it?
In my case it’s not just £10, it’s a raft of extra difficulty.
Which then means young kids running around while she’s sat in the car up on jack stands, tools all over etc.
Then the nipple risk. Moron over-tightened it, leaves you with a car on stands for a week as it shears?
Then the spare brake fluid.
Then disposal.
Or the extra kit again to pressurise the brake reservoir to avoid the need of the wife/kids combo.
It’s seemingly a lot simpler to not go down that path if it’s not necessary isn’t it?
In my case it’s not just £10, it’s a raft of extra difficulty.
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