Rebuild Shimano XT M8000 Lever/Master Cylinder

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Oct 4, 2018
Threads
13
Messages
474
Location
Nova Scrota
They say Shimano levers are not serviceable. But they are.

IMG_20210120_190442~2.jpg
 
Last edited:
Remove the brake hose (the mt8000 uses a 8mm nut hidden under a rubber cover where the hose inserts into the caliper)

Remove the caliper from the handlebar and get as much oil out as you can.

IMG_20210120_185021~2.webp


IMG_20210120_191404~2.webp
 
Last edited:
IMG_20210120_190818~2.webp


Then loosen the set screw located behind the plug. Then you can push out the pin.

IMG_20210120_191138~2.webp


IMG_20210120_191542~2.webp


IMG_20210120_191221.webp


IMG_20210120_191713.webp
 
Last edited:
Now to get the cylinder and spring out...

There's a hinged keeper holding them in. The hinge pin (it's part of the keeper--all one piece) is at the top, and the plastic plate at the top is holding the hinge in place.

Depress the piston and gently pry out the top plastic plate. Gently! If you break it then you're buying a new lever. Actually that goes for everything you're touching in this job. lol

IMG_20210120_193231~2.webp
IMG_20210120_193523~2.webp

IMG_20210120_193855~2.webp
 
Reassemble. If you bought new seals, put them on your piston. Dunk the spring and seals in mineral oil.
IMG_20210120_202112~2.webp
 
Put spring and piston in cylinder bore.

Now you're going to have to fiddle the top plate and hinged keeper into place. Be patient. It's easiest (but still not easy) to put them in together, in the correct anatomical position

Once you've done that, snap the bottom plate back in place (if you removed and cleaned it, like you should have).

Next, twist that push rod back into place. You'll need to compress the piston/spring to get it done. It's pretty fiddly too. Be patient. Maybe use your dad's dental tools.

IMG_20210120_202257~3.webp
 
Last edited:
Now time to reinstall the lever to the body. The big pin should, from top to bottom, go thru:
1. Top of body
2. Top of lever
3. Hole in lever pivot
4. Lever spring
5. Bottom of lever
6. Bottom of body.

The problem here is that you have to line everything up, including the lever spring that you were supposed to note the location and orientation of before disassembly.

I line it all up and hold it In place with a small screwdriver or hex wrench, which I then push out as I replace it by inserting the lever pin.

It's fiddly. Be patient. You'll hate that ****ing lever spring.

IMG_20210120_204904~2.webp


That pic kinda sucks. I mean, it's a great pic, but the screwdriver is pointed the wrong way. Don't do like the picture: insert screwdriver from bottom to top, and push it out with the pin going top to bottom.

Last, DON'T FORGET TO TIGHTEN THE PIN RETAINER and put the little rubber plug back in place.
 
Last edited:
IMG_20210120_210343~2.webp


Cylinder scoring? What cylinder scoring?

Cross fingers your cylinder doesn't look like this:

IMG_20210120_200104~2.webp


If it does, well, you're still probably going to get another year or two out of a bad ass lever. If it looks better than that, then you've got a brand new lever.

Shred on, my shredders!
 

Users who are viewing this thread

Back
Top Bottom