Hi everyone, So I changed my fork for a New one in my Merida and I had to remove the brake to do so.
All the oil dripped out of the system and now I need to fix it.
For now I'm at a stage of a brake hanging loose and I don't know how to proceed from here. I have all the tools but no knowledge how to make them work again.
On top of that, I have changed braking pads and New ones are so tight I can't put braking disc between.
Any help would be very very much grateful!
by cacko321
3 Comments
You need to properly install and bleed your brakes. Your new brake pads don’t fit because the pistons has adjusted to the old thickness.
Go to YouTube and find instructions on how to properly reset the pistons and bleed the brakes. It’s a very involved process and you could do it wrong and contaminate the rotor or brake pads. So unless you have the time to learn to do it properly, best left this to a shop.
Before anything else, why did you lose oil from the system? Did you open the bleed valve or disconnect the hose unnecessarily or is something broken or leaking? If there’s something broken or leaking you won’t be able to get this working again until that’s addressed. But if you only lost some fluid then the solution is to remove the pads and press the pistons back in with a piston press or something soft like a plastic tire lever (don’t use a screwdriver, you can crack the ceramic pistons that way). Once they’re back in place you’ll install a bleed block and then complete a full brake bleed (explaining that is beyond the scope of this reply, see the instructions from Shimano or myriad guides online).
Remove the pads. You never want to bleed your brakes with pads in, otherwise you’ll contaminate them with hydro fluid/oil.
Since all the mineral oil drained it may be difficult to push the pistons in, due to air pressure and temperature changes. Open the bleed valve on the lever.
After removing the pads, push the pistons and install a bleed block. Note, the pistons should be flush with the caliper. It should be easy with an open system.
If the pistons don’t go flush with the caliper, don’t force them or you could do damage. There may be another problem.
Find a video on how to bleed your grx brakes.
Good luck.